Feedforward Contributions to Sensory Response Properties in the Early Visual System

Feedforward Contributions to Sensory Response Properties in the Early Visual System PDF Author: Bartlett Doe Moore
Publisher:
ISBN: 9781124025605
Category :
Languages : en
Pages :

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Book Description
The unique ecological utility provided by the complex sensory processing that occurs in the brains of visual animals cannot be over appreciated. Psychologists, physiologists, mathematicians, and philosophers, among others, have subjected vision in humans and non-human animals to intense scrutiny. Perhaps the most studied regions of the mammalian visual system are the early visual pathways: the retina, the dorsal lateral geniculate nucleus of the thalamus (LGN), and area 17 of the primary visual cortex (V1). This dissertation was conceived and conducted to elucidate some of the contributions of feedforward processes to sensory responses in the early visual system. Extracellular recordings were collected from individual neurons in the retina, visual thalamus, and primary visual cortex of cats, and the primary visual cortex of ferrets while controlling the sensory input to the system. These methods were used to characterize five distinct features of information processing: 1) the influence of stimulus temporal frequency on orientation tuning in V1 neurons, 2) the influence of stimulus temporal frequency on direction selectivity in V1 neurons, 3) the response properties of LGN neurons in the absence of On-center retinal input, 4) the orientation tuning in V1 neurons in the absence of On-center LGN input, and 5) the direction selectivity of V1 neurons in the absence of On-center LGN input. The results presented in the following chapters show that the paradigmatic feedforward model of processing in the early visual system and its contribution to neuronal response properties requires further refinement. The work presented in chapter 2 show that the direction selectivity--but not orientation tuning--of ferret V1 neurons is dependant on the temporal frequency of stimuli, suggesting that stability of orientation tuning is an important aspect of early visual processing. The work presented in chapter 3 suggest there is more frequent divergence of connections in the retinogeniculate pathway of the cat than previously recognized and that functionally silent, non-specific retinal inputs can undergo rapid plasticity when the On pathway is disrupted. The work presented in chapter 4 investigates the response properties of V1 neurons in the absence of On-center LGN activity. The results show that while orientation tuning is resilient to the reduction in feedforward input, direction selectivity behaves more erratically. The early visual system is the computational foundation upon which more complex features are detected in the visual environment. In order to understand how visual processing in later visual pathways is accomplished, it is critical that the feedforward contributions to response properties in the early visual pathways be understood.

Feedforward Contributions to Sensory Response Properties in the Early Visual System

Feedforward Contributions to Sensory Response Properties in the Early Visual System PDF Author: Bartlett Doe Moore
Publisher:
ISBN: 9781124025605
Category :
Languages : en
Pages :

Get Book Here

Book Description
The unique ecological utility provided by the complex sensory processing that occurs in the brains of visual animals cannot be over appreciated. Psychologists, physiologists, mathematicians, and philosophers, among others, have subjected vision in humans and non-human animals to intense scrutiny. Perhaps the most studied regions of the mammalian visual system are the early visual pathways: the retina, the dorsal lateral geniculate nucleus of the thalamus (LGN), and area 17 of the primary visual cortex (V1). This dissertation was conceived and conducted to elucidate some of the contributions of feedforward processes to sensory responses in the early visual system. Extracellular recordings were collected from individual neurons in the retina, visual thalamus, and primary visual cortex of cats, and the primary visual cortex of ferrets while controlling the sensory input to the system. These methods were used to characterize five distinct features of information processing: 1) the influence of stimulus temporal frequency on orientation tuning in V1 neurons, 2) the influence of stimulus temporal frequency on direction selectivity in V1 neurons, 3) the response properties of LGN neurons in the absence of On-center retinal input, 4) the orientation tuning in V1 neurons in the absence of On-center LGN input, and 5) the direction selectivity of V1 neurons in the absence of On-center LGN input. The results presented in the following chapters show that the paradigmatic feedforward model of processing in the early visual system and its contribution to neuronal response properties requires further refinement. The work presented in chapter 2 show that the direction selectivity--but not orientation tuning--of ferret V1 neurons is dependant on the temporal frequency of stimuli, suggesting that stability of orientation tuning is an important aspect of early visual processing. The work presented in chapter 3 suggest there is more frequent divergence of connections in the retinogeniculate pathway of the cat than previously recognized and that functionally silent, non-specific retinal inputs can undergo rapid plasticity when the On pathway is disrupted. The work presented in chapter 4 investigates the response properties of V1 neurons in the absence of On-center LGN activity. The results show that while orientation tuning is resilient to the reduction in feedforward input, direction selectivity behaves more erratically. The early visual system is the computational foundation upon which more complex features are detected in the visual environment. In order to understand how visual processing in later visual pathways is accomplished, it is critical that the feedforward contributions to response properties in the early visual pathways be understood.

Sensory Processing in the Early Visual System

Sensory Processing in the Early Visual System PDF Author: Henry Joseph Alitto
Publisher:
ISBN:
Category :
Languages : en
Pages : 352

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Book Description


Feedforward and Feedback Processes in Vision

Feedforward and Feedback Processes in Vision PDF Author: Hulusi Kafaligonul
Publisher: Frontiers Media SA
ISBN: 2889195945
Category : Feedback
Languages : en
Pages : 153

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Book Description
The visual system consists of hierarchically organized distinct anatomical areas functionally specialized for processing different aspects of a visual object (Felleman & Van Essen, 1991). These visual areas are interconnected through ascending feedforward projections, descending feedback projections, and projections from neural structures at the same hierarchical level (Lamme et al., 1998). Accumulating evidence from anatomical, functional and theoretical studies suggests that these three projections play fundamentally different roles in perception. However, their distinct functional roles in visual processing are still subject to debate (Lamme & Roelfsema, 2000). The focus of this Research Topic is the roles of feedforward and feedback projections in vision. Even though the notions of feedforward, feedback, and reentrant processing are widely accepted, it has been found difficult to distinguish their individual roles on the basis of a single criterion. We welcome empirical contributions, theoretical contributions and reviews that fit into any one (or a combination) of the following domains: 1) their functional roles for perception of specific features of a visual object 2) their contributions to the distinct modes of visual processing (e.g., pre-attentive vs. attentive, conscious vs. unconscious) 3) recent techniques/methodologies to identify distinct functional roles of feedforward and feedback projections and corresponding neural signatures. We believe that the current Research Topic will not only provide recent information about feedforward/feedback processes in vision but also contribute to the understanding fundamental principles of cortical processing in general.

Vision

Vision PDF Author: David Marr
Publisher: MIT Press
ISBN: 0262514621
Category : Psychology
Languages : en
Pages : 429

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Book Description
Available again, an influential book that offers a framework for understanding visual perception and considers fundamental questions about the brain and its functions. David Marr's posthumously published Vision (1982) influenced a generation of brain and cognitive scientists, inspiring many to enter the field. In Vision, Marr describes a general framework for understanding visual perception and touches on broader questions about how the brain and its functions can be studied and understood. Researchers from a range of brain and cognitive sciences have long valued Marr's creativity, intellectual power, and ability to integrate insights and data from neuroscience, psychology, and computation. This MIT Press edition makes Marr's influential work available to a new generation of students and scientists. In Marr's framework, the process of vision constructs a set of representations, starting from a description of the input image and culminating with a description of three-dimensional objects in the surrounding environment. A central theme, and one that has had far-reaching influence in both neuroscience and cognitive science, is the notion of different levels of analysis—in Marr's framework, the computational level, the algorithmic level, and the hardware implementation level. Now, thirty years later, the main problems that occupied Marr remain fundamental open problems in the study of perception. Vision provides inspiration for the continuing efforts to integrate knowledge from cognition and computation to understand vision and the brain.

A Combined MRI and Histology Atlas of the Rhesus Monkey Brain in Stereotaxic Coordinates

A Combined MRI and Histology Atlas of the Rhesus Monkey Brain in Stereotaxic Coordinates PDF Author: Kadharbatcha S. Saleem
Publisher: Academic Press
ISBN: 0123850878
Category : Medical
Languages : en
Pages : 402

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Book Description
A Combined MRI and Histology Atlas of the Rhesus Monkey Brain in Stereotaxic Coordinates, Second Edition maps the detailed architectonic subdivisions of the cortical and subcortical areas in the macaque monkey brain using high-resolution magnetic resonance (MR) images and the corresponding histology sections in the same animal. This edition of the atlas is unlike anything else available as it includes the detailed cyto- and chemoarchitectonic delineations of the brain areas in all three planes of sections (horizontal, coronal, and sagittal) that are derived from the same animal. This is a significant progress because in functional imaging studies, such as fMRI, both the horizontal and sagittal planes of sections are often the preferred planes given that multiple functionally active regions can be visualized simultaneously in a single horizontal or sagittal section. This combined MRI and histology atlas is designed to provide an easy-to-use reference for anatomical and physiological studies in macaque monkeys, and in functional-imaging studies in human and non-human primates using fMRI and PET. The first rhesus monkey brain atlas with horizontal, coronal, and sagittal planes of sections, derived from the same animal Shows the first detailed delineations of the cortical and subcortical areas in horizontal, coronal, and sagittal plane of sections in the same animal using different staining methods Horizonal series illustrates the dorsoventral extent of the left hemisphere in 47 horizontal MRI and photomicrographic sections matched with 47 detailed diagrams (Chapter 3) Coronal series presents the full rostrocaudal extent of the right hemisphere in 76 coronal MRI and photomicrographic sections, with 76 corresponding drawings (Chapter 4) Sagittal series shows the complete mediolateral extent of the left hemisphere in 30 sagittal MRI sections, with 30 corresponding drawings (Chapter 5). The sagittal series also illustrates the location of different fiber tracts in the white matter Individual variability - provides selected cortical and subcortical areas in three-dimensional MRI (horizontal, coronal, and sagittal MRI planes). For comparison, it also provides similar areas in coronal MRI section in six other monkeys. (Chapter 6) Vasculature - indicates the corresponding location of all major blood vessels in horizontal, coronal, and sagittal series of sections Provides updated information on the cortical and subcortical areas, such as architectonic areas and nomenclature, with references, in chapter 2 Provides the sterotaxic grid derived from the in-vivo MR image

Microcircuits

Microcircuits PDF Author: Sten Grillner
Publisher: MIT Press
ISBN: 0262072785
Category : Anatomy
Languages : en
Pages : 471

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Book Description
Leading neuroscientists discuss the function of microcircuits, functional modules that act as elementary processing units bridging single cells to systems and behavior. Microcircuits, functional modules that act as elementary processing units bridging single cells to systems and behavior, could provide the link between neurons and global brain function. Microcircuits are designed to serve particular functions; examples of these functional modules include the cortical columns in sensory cortici, glomeruli in the olfactory systems of insects and vertebrates, and networks generating different aspects of motor behavior. In this Dahlem Workshop volume, leading neuroscientists discuss how microcircuits work to bridge the single cell and systems levels and compare the intrinsic function of microcircuits with their ion channel subtypes, connectivity, and receptors, in order to understand the design principles and function of the microcircuits. The chapters cover the four major areas of microcircuit research: motor systems, including locomotion, respiration, and the saccadic eye movements; the striatum, the largest input station of the basal ganglia; olfactory systems and the neural organization of the glomeruli; and the neocortex. Each chapter is followed by a group report, a collaborative discussion among senior scientists. Contributors Lidia Alonso-Nanclares, Hagai Bergman, Maria Blatow, J. Paul Bolam, Ansgar Büschges, Antonio Caputi, Jean-Pierre Changeux, Javier DeFelipe, Carsten Duch, Paul Feinstein, Stuart Firestein, Yves Frégnac, Rainer W. Friedrich, C. Giovanni Galizia, Ann M. Graybiel, Charles A. Greer, Sten Grillner, Tadashi Isa, Ole Kiehn, Minoru Kimura, Anders Lanser, Gilles Laurent, Pierre-Marie Lledo, Wolfgang Maass, Henry Markram, David A. McCormick, Christoph M. Michel, Peter Mombaerts, Hannah Monyer, Hans-Joachim Pflüger, Dietmar Plenz, Diethelm W. Richter, Silke Sachse, H. Sebastian Seung, Keith T. Sillar, Jeffrey C. Smith, David L. Sparks, D. James Surmeier, Eörs Szathmáry, James M. Tepper, Jeff R. Wickens, Rafael Yuste

The Senses: A Comprehensive Reference

The Senses: A Comprehensive Reference PDF Author:
Publisher: Academic Press
ISBN: 0128054093
Category : Medical
Languages : en
Pages : 5215

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Book Description
The Senses: A Comprehensive Reference, Second Edition, Seven Volume Set is a comprehensive reference work covering the range of topics that constitute current knowledge of the neural mechanisms underlying the different senses. This important work provides the most up-to-date, cutting-edge, comprehensive reference combining volumes on all major sensory modalities in one set. Offering 264 chapters from a distinguished team of international experts, The Senses lays out current knowledge on the anatomy, physiology, and molecular biology of sensory organs, in a collection of comprehensive chapters spanning 4 volumes. Topics covered include the perception, psychophysics, and higher order processing of sensory information, as well as disorders and new diagnostic and treatment methods. Written for a wide audience, this reference work provides students, scholars, medical doctors, as well as anyone interested in neuroscience, a comprehensive overview of the knowledge accumulated on the function of sense organs, sensory systems, and how the brain processes sensory input. As with the first edition, contributions from leading scholars from around the world will ensure The Senses offers a truly international portrait of sensory physiology. The set is the definitive reference on sensory neuroscience and provides the ultimate entry point into the review and original literature in Sensory Neuroscience enabling students and scientists to delve into the subject and deepen their knowledge. All-inclusive coverage of topics: updated edition offers readers the only current reference available covering neurobiology, physiology, anatomy, and molecular biology of sense organs and the processing of sensory information in the brain Authoritative content: world-leading contributors provide readers with a reputable, dynamic and authoritative account of the topics under discussion Comprehensive-style content: in-depth, complex coverage of topics offers students at upper undergraduate level and above full insight into topics under discussion

The Rhesus Monkey Brain in Stereotaxic Coordinates

The Rhesus Monkey Brain in Stereotaxic Coordinates PDF Author: George Paxinos
Publisher: Academic Press
ISBN: 0128158530
Category : Medical
Languages : en
Pages : 394

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Book Description
Paxinos and Petrides' The Rhesus Monkey Brain in Stereotaxic Coordinates is the most comprehensive and accurate atlas of the monkey brain currently available. The fourth edition of this classic book will be a complete revision, featuring many improvements and upgrades. Containing coronal diagrams and accompanying photographic plates spaced at 120 μm intervals, this atlas follows the same nomenclature and abbreviations conventions as the mouse, rat, chicken, and human brain atlases published under George Paxinos’ leadership. This atlas is suitable for researchers who work with both monkeys and humans. Constructed by the established leaders in neuroanatomical atlas development, the new edition will again be the indispensable resource for all scientists working on the primate nervous system. 141 completely revised coronal diagrams and accompanying colour photographic plates spaced at approximately 120 μm intervals 60 colour photographic coronal plates of SMI immunoreactivity with completely revised delineations Includes MR images at approximately the same levels as the coronal diagrams Follows the same nomenclature and abbreviations as the mouse, rat, chicken, marmoset and human brain atlases, with indications of correspondence to alternative macaque nomenclatures This atlas was used for the delineation and nomenclature of MRI-based macaque brain atlases for neuroimaging analyses, including the SARM

Filling-in

Filling-in PDF Author: Luiz Pessoa
Publisher: Oxford University Press, USA
ISBN: 0195140133
Category : Medical
Languages : en
Pages : 369

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Book Description
The best example of filling-in involves the blind spot, a region of the retina devoid of photoreceptors. While this phenomenon is common in the visual domain, it is argued by contributors to this book that forms of filling-in also take place in other sensory modalities.

Inhibitory Synaptic Plasticity

Inhibitory Synaptic Plasticity PDF Author: Melanie A. Woodin
Publisher: Springer Science & Business Media
ISBN: 1441969780
Category : Medical
Languages : en
Pages : 191

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Book Description
This volume will explore the most recent findings on cellular mechanisms of inhibitory plasticity and its functional role in shaping neuronal circuits, their rewiring in response to experience, drug addiction and in neuropathology. Inhibitory Synaptic Plasticity will be of particular interest to neuroscientists and neurophysiologists.