Cortical Circuits

Cortical Circuits

PartII Functional Aspects of Cortical Circuitry AsafKeller Part Ipresented the anatomical basisfor corticalcircuitry: the various neuronal typesand the synaptic connections betweenthem. The aim ofPartII istwofold: first,toprovide data ...

Author: WHITE

Publisher: Springer Science & Business Media

ISBN: 9781468487213

Category: Medical

Page: 224

View: 519

This elegant book presents current evidence on the organization of the mammalian cerebral cortex. The focus on synapses and their function provides the basis for understanding how this critical part of the brain could work. Dr. White and his colleague Dr. Keller have collated an impressive mass of material. This makes the crucial information accessible and coherent. Dr. White pioneered an area of investigation that to most others, and occasionally to himself, seemed a bottomless pit of painstaking at tention to detail for the identification and enumeration of cortical syn apses. I do not recall that he or anyone else suspected, when he began to publish his now classic papers, that the work would be central to an accelerating convergence of information and ideas from neurobiology and computer science, especially artificial intelligence (AI) (Rumelhart and McClelland, 1986). The brain is the principal organ responsible for the adaptive capacities of animals. What has impressed students of biology, of medicine, and, to an extent, of philosophy is the correlation between the prominence of the cerebral cortex and the adaptive "complexity" of a particular spe cies. Most agree that the cortex is what sets Homo sapiens apart from other species quantitatively and qualitatively (Rakic, 1988). This is summarized in the first chapter.
Categories: Medical

Local Cortical Circuits

Local Cortical Circuits

... Moshe, 1936-Local cortical circuits. (Studies of brain function ; v. 6) Bibliography: p. Includes index. 1. Neural circuitry. 2. Cerebral cortex. 3. Action potentials (Electrophysiology) I. Title. II. Series. [DNLM: 1.

Author: Moshe Abeles

Publisher: Springer Science & Business Media

ISBN: 9783642817083

Category: Medical

Page: 104

View: 163

Neurophysiologists are often accused by colleagues in the physical sci ences of designing experiments without any underlying hypothesis. This impression is attributable to the ease of getting lost in the ever-increasing sea of professional publications which do not state explicitly the ultimate goal of the research. On the other hand, many of the explicit models for brain function in the past were so far removed from experimental reality that they had very little impact on further research. It seems that one needs much intimate experience with the real nerv-. ous system before a reasonable model can be suggested. It would have been impossible for Copernicus to suggest his model of the solar system without the detailed observations and tabulations of star and planet motion accu mulated by the preceeding generations. This need for intimate experience with the nervous system before daring to put forward some hypothesis about its mechanism of action is especially apparent when theorizing about cerebral cortex function. There is widespread agreement that processing of information in the cor tex is associated with complex spatio-temporal patterns of activity. Yet the vast majority of experimental work is based on single neuron recordings or on recordings made with gross electrodes to which tens of thousands of neurons contribute in an unknown fashion. Although these experiments have taught us a great deal about the organization and function of the cor tex, they have not enabled us to examine the spatio-temporal organization of neuronal activity in any detail.
Categories: Medical

Visual Attention and Cortical Circuits

Visual Attention and Cortical Circuits

of theory seeks to build upon a general knowledge of visual function and cortical circuits , which a priori has nothing to do with attention ( second theory in chapter 10 , chapters 11 and 13 ) . In its most developed form , such a ...

Author: Jochen Braun

Publisher: MIT Press

ISBN: 0262024934

Category: Medical

Page: 358

View: 680

An attempt to derive a comprehensive theory of attention from both neurobiological and psychological data. The neurobiology and psychology of attention have much to learn from each other. Neurobiologists recognize that responses in sensory cortex depend on the behavioral relevance of a stimulus, but have few ways to study how perception changes as a result. Psychologists have the conceptual and methodological tools to do just that, but are confounded by the multiple interpretations and theoretical ambiguities. This book attempts to bridge the two fields and to derive a comprehensive theory of attention from both neurobiological and psychological data. It highlights situations where attention can be seen to alter both neural activity and psychophysical performance/phenomenal experience. This bicultural approach contributes not only to attention research but to the larger goal of linking neural activity to conscious experience. The book focuses mainly on the effects of visual attention on the ventral and dorsal streams of visual cortex in humans and monkeys and the associated changes in visual performance. Several larger findings emerge: attention may involve more than one neural system; attention modulates all stages of cortical visual processing; the effect of attention is constrained by the intrinsic connectivity of cortex and the resulting contextual interactions; and the notion of a saliency map remains central to thinking about visual attention. The book also considers several approaches to evaluating the same variable through different methods, such as behavioral measurements, functional imaging, and single-unit recording. Contributors Narcisse P. Bichot, Erik Blaser, Geoffrey M. Boynton, Jochen Braun, Maurizio Corbetta, Sean M. Culhane, Florin Cutzu, Sophie Deneve, Robert Desimone, John Duncan, Sunil P. Gandhi, Charles D. Gilbert, David J. Heeger, James W. Holsapple, Alexander C. Huk, Minami Ito, Laurent Itti, Christof Koch, Peter E. Latham, Nilli Lavie, D. Kathleen Lee, Zhong-Lin Lu, John H.R. Maunsell, Carrie J. McAdams, Brad C. Motter, Alexandre Pouget, Adam Reeves, John H. Reynolds, Jeffrey D. Schall, Christian Scheier, Shinsuke Shimojo, Gordon L. Shulman, George Sperling, Kirk G. Thompson, John K. Tsotsos, Katsumi Watanabe, Erich Weichselgartner, Gerald Westheimer
Categories: Medical

Fast Oscillations in Cortical Circuits

Fast Oscillations in Cortical Circuits

Library of Congress Cataloging - in - Publication Data Traub , Roger D. Fast oscillations in cortical circuits / Roger D. Traub , John G.R. Jefferys , and Miles A. Whittington . p . cm . ( Computational neuroscience ) " Bradford book .

Author: Roger D. Traub

Publisher: MIT Press

ISBN: 0262201186

Category: Medical

Page: 364

View: 534

In Fast Oscillations in Cortical Circuits, the authors use a combination of electrophysiological and computer modeling techniques to analyze how large networks of neurons can produce both epileptic seizures and functionally relevant synchronized oscillations.
Categories: Medical

The Ontogenesis of Cortical Circuitry The Spatial Distribution of Synapses in Somesthetic Cortex of Newborn Dog

The Ontogenesis of Cortical Circuitry  The Spatial Distribution of Synapses in Somesthetic Cortex of Newborn Dog

On the basis of the results obtained in the present study, we believe that the quantitative analysis of synapse distributions is a practical and meaningful approach to the study of developing cortical circuitry.

Author: M. E. Molliver

Publisher: Springer Science & Business Media

ISBN: 9783642516313

Category: Medical

Page: 54

View: 769

The ontogenesis of cortical circuitry is the subject of the investigation reported in this paper!. Strategie elements of cortical circuitry are synaptic contacts: sites of neuronal interaction. If we first determine the location of early formed synap ses, we may then seek the pre-and postsynaptic elements, that is, the structures which meet and interact at each synaptic junction. The dynamic aspects of cortical development cannot be studied directly: neuronal growth cannot be observed in an intact brain. The pattern of develop ment can be approached only by the analysis of static properties at multiple ages. We have selected the newborn dog as a starting point for these studies. Our observations have been restricted to a small portion of primary somesthetic cor tex. This region was selected because, in mature cortex, its input and physiologie properties are relatively weIl known. It is particularly advantageous to study a primary sensory projection area because its morphologie development can be di rectly related to its functional development. (A related investigation of the onto genesis of electrical activity in somesthetic cortex of the dog will be reported separately). A selective review of the literature is necessary in order to place this work in the context of a few relevant phenomena of cortical development.
Categories: Medical

Cortical Areas

Cortical Areas

Theoretical studies also suggest that intrinsic cortical circuits may play an important role in generation of basic receptive field properties, either by amplifying weakly-tuned thalamic afferent signals (Somers etal., 1995) or even by ...

Author: Almut Schuez

Publisher: CRC Press

ISBN: 9780203299296

Category: Medical

Page: 533

View: 379

The study of areas in the cerebral cortex has a long history, bringing empirical data into close relation with fundamental conceptual issues about the cortex. The subject is currently being revitalized with the advent of new experimental methods and this book brings a modern perspective to the study of these areas. Cortical Areas: Unity and Diversi
Categories: Medical

Cortical Connectivity

Cortical Connectivity

Circuits. for. I-Wave. Generations. Corticospinal neurons are among the largest neurons in the brain and are located in layer V of cerebral cortex. They receive inputs from facilitatory interneurons in the M1 (Patton and Amassian 1954).

Author: Robert Chen

Publisher: Springer Science & Business Media

ISBN: 9783642327667

Category: Medical

Page: 361

View: 903

The study and modulation of cortical connections is a rapidly growing area in neuroscience. This unique book by prominent researchers in the field covers recent advances in this area. The first section of the book describes studies of cortical connections, modulation of cortical connectivity and changes in cortical connections with activities such as motor learning and grasping in primates. The second section covers the use of non-invasive brain stimulation to study and modulate cortical connectivity in humans. The last section describes changes in brain connectivity in neurological and psychiatric diseases, and potential new treatments that manipulate brain connectivity. This book provides an up-to-date view of the study of cortical connectivity, and covers its role in both fundamental neuroscience and potential clinical applications.
Categories: Medical

Cortical Subcortical Loops in Sensory Processing

Cortical Subcortical Loops in Sensory Processing

to the cortex (Petrus et al., 2014, 2015; Rodríguez et al., 2018) as well as functional refinement of the cortical circuits (Meng et al., 2015, 2017; Solarana et al., 2019). Cellular mechanisms underlying these two distinct plasticity ...

Author: Max F. K. Happel

Publisher: Frontiers Media SA

ISBN: 9782889745852

Category: Science

Page: 253

View: 801

Categories: Science

Cortical GABAergic neurons stretching it

Cortical GABAergic neurons  stretching it

providing feed-forward excitation to the developing cortical circuits subplate neurons can regulate both the maturation of glutamatergic thalamocortical and GABAergic intracortical synapses. By controlling cortical inhibition, ...

Author: Javier DeFelipe

Publisher: Frontiers E-books

ISBN: 9782889190379

Category:

Page: 89

View: 870

In the cerebellum and basal ganglia, projection neurons are GABAergic; but in the cerebral cortex, there has been a historically strong dichotomy between glutamatergic projection neurons and GABAergic local circuit neurons. While this dichotomy is overwhelmingly the case, it is now clear that a small population of long-distance projecting GABAergic neurons (positive for somatostatin and nNOS, and negative for parvalbumin) occurs in primates, as well as in cats and rodents. Beyond their well-documented existence, however, the functional significance, ontogeny, and connectivity of this intriguing subpopulation remain obscure.
Categories:

Cortical Development

Cortical Development

Cortical. Circuit. Formation. F.M. Rodríguez-Tornos et al. The mammalian neocortex is a complex, highly organized ... Certain cortical circuits are also preserved among species throughout evolution, while new circuits and functions have ...

Author: Ryoichiro Kageyama

Publisher: Springer Science & Business Media

ISBN: 9784431544968

Category: Medical

Page: 282

View: 494

This book reviews recent progress in cortical development research, focusing on the mechanisms of neural stem cell regulation, neuronal diversity and connectivity formation, and neocortical organization. Development of the cerebral cortex, the center for higher brain functions such as cognition, memory, and decision making, is one of the major targets of current research. The cerebral cortex is divided into many areas, including motor, sensory, and visual cortices, each of which consists of six layers containing a variety of neurons with different activities and connections. As this book explains, such diversity in neuronal types and connections is generated at various levels. First, neural stem cells change their competency over time, giving sequential rise to distinct types of neurons and glial cells: initially deep layer neurons, then superficial layer neurons, and lastly astrocytes. The activities and connections of neurons are further modulated via interactions with other brain regions, such as the thalamocortical circuit, and via input from the environment. This book on cortical development is essential reading for students, postdocs, and neurobiologists.
Categories: Medical