Retinal Computation PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Retinal Computation PDF full book. Access full book title Retinal Computation by Greg Schwartz. Download full books in PDF and EPUB format.
Author: Greg Schwartz
Publisher: Academic Press
ISBN: 0128231777
Category : Medical
Languages : en
Pages : 342
Get Book Here
Book Description
Retinal Computation summarizes current progress in defining the computations performed by the retina, also including the synaptic and circuit mechanisms by which they are implemented. Each chapter focuses on a single retinal computation that includes the definition of the computation and its neuroethological purpose, along with the available information on its known and unknown neuronal mechanisms. All chapters contain end-of-chapter questions associated with a landmark paper, as well as programming exercises. This book is written for advanced graduate students, researchers and ophthalmologists interested in vision science or computational neuroscience of sensory systems. While the typical textbook's description of the retina is akin to a biological video camera, the real retina is actually the world’s most complex image processing machine. As part of the central nervous system, the retina converts patterns of light at the input into a rich palette of representations at the output. The parallel streams of information in the optic nerve encode features like color, contrast, orientation of edges, and direction of motion. Image processing in the retina is undeniably complex, but as one of the most accessible parts of the central nervous system, the tools to study retinal circuits with unprecedented precision are up to the task. This book provides a practical guide and resource about the current state of the field of retinal computation. Provides a practical guide on the field of retinal computation Summarizes and clearly explains important topics such as luminance, contrast, spatial features, motion and other computations Contains discussion questions, a landmark paper, and programming exercises within each chapter
Author: Greg Schwartz
Publisher: Academic Press
ISBN: 0128231777
Category : Medical
Languages : en
Pages : 342
Get Book Here
Book Description
Retinal Computation summarizes current progress in defining the computations performed by the retina, also including the synaptic and circuit mechanisms by which they are implemented. Each chapter focuses on a single retinal computation that includes the definition of the computation and its neuroethological purpose, along with the available information on its known and unknown neuronal mechanisms. All chapters contain end-of-chapter questions associated with a landmark paper, as well as programming exercises. This book is written for advanced graduate students, researchers and ophthalmologists interested in vision science or computational neuroscience of sensory systems. While the typical textbook's description of the retina is akin to a biological video camera, the real retina is actually the world’s most complex image processing machine. As part of the central nervous system, the retina converts patterns of light at the input into a rich palette of representations at the output. The parallel streams of information in the optic nerve encode features like color, contrast, orientation of edges, and direction of motion. Image processing in the retina is undeniably complex, but as one of the most accessible parts of the central nervous system, the tools to study retinal circuits with unprecedented precision are up to the task. This book provides a practical guide and resource about the current state of the field of retinal computation. Provides a practical guide on the field of retinal computation Summarizes and clearly explains important topics such as luminance, contrast, spatial features, motion and other computations Contains discussion questions, a landmark paper, and programming exercises within each chapter
Author: Emanuele Trucco
Publisher: Academic Press
ISBN: 0081028164
Category : Computers
Languages : en
Pages : 504
Get Book Here
Book Description
Computational Retinal Image Analysis: Tools, Applications and Perspectives gives an overview of contemporary retinal image analysis (RIA) in the context of healthcare informatics and artificial intelligence. Specifically, it provides a history of the field, the clinical motivation for RIA, technical foundations (image acquisition modalities, instruments), computational techniques for essential operations, lesion detection (e.g. optic disc in glaucoma, microaneurysms in diabetes) and validation, as well as insights into current investigations drawing from artificial intelligence and big data. This comprehensive reference is ideal for researchers and graduate students in retinal image analysis, computational ophthalmology, artificial intelligence, biomedical engineering, health informatics, and more. Provides a unique, well-structured and integrated overview of retinal image analysis Gives insights into future areas, such as large-scale screening programs, precision medicine, and computer-assisted eye care Includes plans and aspirations of companies and professional bodies
Author: Philip R. Mardoum
Publisher:
ISBN:
Category :
Languages : en
Pages : 83
Get Book Here
Book Description
To understand neural circuit function, one would like to understand individual neurons' computation in the context of their physiological inputs. But these inputs are themselves subject to complex dynamics, and we rarely have tools to experimentally control synaptic inputs under physiological conditions that preserve their temporal features. Primary sensory structures present an exception because primary receptor neurons can be controlled experimentally under physiological conditions. Here, I present work carried out in the retina, where signaling by photoreceptors (the primary receptor neurons in vision) has been characterized in detail and can be controlled with light, and computation in downstream circuitry can therefore be investigated in the context of physiological input from photoreceptors. I first present a hybrid biophysical-statistical model of retinal output that disentangles the computational contributions of photoreceptors from those of other circuit elements and successfully predicts retinal ganglion cell responses to stimuli with dynamically changing statistics. Second, I present an investigation of synaptic specializations that could mediate parallel processing of input from different photoreceptor types within individual post-synaptic neurons.
Author: John P. Frisby
Publisher: MIT Press
ISBN: 0262514273
Category : Psychology
Languages : en
Pages : 577
Get Book Here
Book Description
An accessible yet rigorous and generously illustrated exploration of the computational approach to the study of biological vision. Seeing has puzzled scientists and philosophers for centuries and it continues to do so. This new edition of a classic text offers an accessible but rigorous introduction to the computational approach to understanding biological visual systems. The authors of Seeing, taking as their premise David Marr's statement that “to understand vision by studying only neurons is like trying to understand bird flight by studying only feathers,” make use of Marr's three different levels of analysis in the study of vision: the computational level, the algorithmic level, and the hardware implementation level. Each chapter applies this approach to a different topic in vision by examining the problems the visual system encounters in interpreting retinal images and the constraints available to solve these problems; the algorithms that can realize the solution; and the implementation of these algorithms in neurons. Seeing has been thoroughly updated for this edition and expanded to more than three times its original length. It is designed to lead the reader through the problems of vision, from the common (but mistaken) idea that seeing consists just of making pictures in the brain to the minutiae of how neurons collectively encode the visual features that underpin seeing. Although it assumes no prior knowledge of the field, some chapters present advanced material. This makes it the only textbook suitable for both undergraduate and graduate students that takes a consistently computational perspective, offering a firm conceptual basis for tackling the vast literature on vision. It covers a wide range of topics, including aftereffects, the retina, receptive fields, object recognition, brain maps, Bayesian perception, motion, color, and stereopsis. MatLab code is available on the book's website, which includes a simple demonstration of image convolution.
Author: Sumeet Dua
Publisher: World Scientific
ISBN: 9814462055
Category : Technology & Engineering
Languages : en
Pages : 467
Get Book Here
Book Description
Advances in semi-automated high-throughput image data collection routines, coupled with a decline in storage costs and an increase in high-performance computing solutions have led to an exponential surge in data collected by biomedical scientists and medical practitioners. Interpreting this raw data is a challenging task, and nowhere is this more evident than in the field of opthalmology. The sheer speed at which data on cataracts, diabetic retinopathy, glaucoma and other eye disorders are collected, makes it impossible for the human observer to directly monitor subtle, yet critical details.This book is a novel and well-timed endeavor to present, in an amalgamated format, computational image modeling methods as applied to various extrinsic scientific problems in ophthalmology. It is self-contained and presents a highly comprehensive array of image modeling algorithms and methodologies relevant to ophthalmologic problems. The book is the first of its kind, bringing eye imaging and multi-dimensional hyperspectral imaging and data fusion of the human eye, into focus.The editors are at the top of their fields and bring a strong multidisciplinary synergy to this visionary volume. Their “inverted-pyramid” approach in presenting the content, and focus on core applications, will appeal to students and practitioners in the field.
Author: David B. Kastner
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Adaptation provides a ubiquitous strategy for neural circuits to encode their inputs using their limited dynamic range within the variety of sensory environments that they encounter. However, because of the inherent timescale necessary to optimize the response properties of a cell to its environment, any form of adaptive plasticity can cause a neuron to fail to encode the stimulus when the environment changes. Many ganglion cells, the output neurons of the retina, adapt so as to lower their sensitivity in an environment of high contrast, but if the contrast subsequently decreases the cell will fall below threshold and fail to signal. I have found a distinct form of plasticity within the retina that acts in coordination with the process of adaptation. Cells using this new form of plasticity elevate their sensitivity after a transition to low contrast. This process, called sensitization, occurs in retinas from multiple species. Multielectrode recordings from sensitizing and adapting cells indicate that both populations encode the same visual signals. The complementary action of the two populations helps the retina encode its input over a broader range of signals and environmental changes, with one population continuing to respond when the other fails. The threshold placement of these two cell types further enhances their coordination because sensitizing cells maintain lower thresholds, while adapting cells maintain higher thresholds. Using a theoretical model, I was able to show that this behavior maximized the amount of information that the two populations can provide about their input. I have further studied the spatiotemporal region that controlled the sensitivity of a cell--the adaptive field. Just as retinal circuitry uses excitation and inhibition to form biphasic center-surround receptive fields, the retina can also use adaptation and sensitization to form biphasic adaptive fields in both the spatial and temporal domains. Since visual statistics are correlated across time and space, center-surround biphasic receptive fields more efficiently encode the input by subtracting a prediction of the stimulus so as to just encode the deviation from that prediction. Biphasic adaptive fields appear to perform an opposite function, transmitting a prediction of the stimulus at the transition of a stimulus environment to weaker signals. This assists in the encoding of an uncertain environment by storing features of a predictable input. A model indicates that sensitization within the adaptive field can be produced by adapting inhibition, a form of plasticity whose function was previously unknown. Using pharmacology, I confirmed this prediction, showing that GABAergic inhibition is necessary for sensitization. Using simultaneous intracellular recording from inhibitory amacrine cells and multielectrode recording from ganglion cells, I show that transmission from a single amacrine cell is sucient to cause sensitization. Using a novel approach to analyze a circuit, I quantitatively describe the changes in amacrine cell transmission that underlie sensitization thus elucidating how the retina performs this sophisticated computation.
Author: José Mira
Publisher: Springer Science & Business Media
ISBN: 9783540567981
Category : Computers
Languages : en
Pages : 772
Get Book Here
Book Description
Neural computation arises from the capacity of nervous tissue to process information and accumulate knowledge in an intelligent manner. Conventional computational machines have encountered enormous difficulties in duplicatingsuch functionalities. This has given rise to the development of Artificial Neural Networks where computation is distributed over a great number of local processing elements with a high degree of connectivityand in which external programming is replaced with supervised and unsupervised learning. The papers presented in this volume are carefully reviewed versions of the talks delivered at the International Workshop on Artificial Neural Networks (IWANN '93) organized by the Universities of Catalonia and the Spanish Open University at Madrid and held at Barcelona, Spain, in June 1993. The 111 papers are organized in seven sections: biological perspectives, mathematical models, learning, self-organizing networks, neural software, hardware implementation, and applications (in five subsections: signal processing and pattern recognition, communications, artificial vision, control and robotics, and other applications).
Author: William E. Schiesser
Publisher: Academic Press
ISBN: 0128184531
Category : Science
Languages : en
Pages : 144
Get Book Here
Book Description
Numerical PDE Analysis of Retinal Neovascularization Mathematical Model Computer Implementation in R provides a methodology for the analysis of neovascularization (formation of blood capillaries) in the retina. It describes the starting point—a system of three partial differential equations (PDEs)—that define the evolution of (1) capillary tip density, (2) blood capillary density and (3) concentration of vascular endothelial growth factor (VEGF) in the retina as a function of space (distance along the retina), x, and time, t, the three PDE dependent variables for (1), (2) and (3), and designated as u1(x, t), u2(x, t), u3(x, t), amongst other topics. Includes PDE routines based on the method of lines (MOL) for computer-based implementation of PDE models Offers transportable computer source codes for readers in R, with line-by-line code descriptions as it relates to the mathematical model and algorithms Authored by a leading researcher and educator in PDE models
Author: Matthias Wulf
Publisher: IOS Press
ISBN: 9783898382540
Category : Computational neuroscience
Languages : en
Pages : 356
Get Book Here
Book Description
Author: Jo?o C. Martins
Publisher: World Scientific
ISBN: 981279431X
Category : Medical
Languages : en
Pages : 271
Get Book Here
Book Description
This book provides a sound mathematical and technical perspective in functional and structural retina models, presents evaluation metrics to assess those models, and provides insights about the models hardware implementation.
