Download or read book Seeing Without Rods Or Cones Contributions of Intrinsically photosensitive Retinal Ganglion Cells to the Image forming Visual System written by Stewart Madon and published by . This book was released on 2013 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: "It was long thought that rods and cones were the only components of the mammalian retina capable of conveying light information to the brain. Recently, a novel class of transduction-capable retinal ganglion cells containing the photopigment melanopsin were discovered in the mammalian retina identified as an “intrinsically photosensitive retinal ganglion cell” or ipRGC. Most of the functionality associated with ipRGCs has been linked to nonperceptual, non-cortical visual operations such as circadian (day-night) phase modulation and pupillary constriction. More recently, however, two subpopulations of ipRGCs have been identified called M1 and M2 cells, with the latter showing “blue-yellow” chromatic opponency that possibly links to brightness or colour pattern vision – properties associated with the retinogeniculostriate, or image-forming visual system. The present study expands on the current understanding of these putative image-forming non-traditional photoreceptor systems. To this end, I developed two stimulus paradigms that target short-wavelength-sensitive cones (S-cones) to tease out the unique contributions of ipRGCs that have neural associations with S-cone visual functioning. In the first paradigm, I measured detection thresholds using short-wavelength selective stimuli that are temporally presented with either an onset or offset “sawtooth” profile to ascertain ipRGC input to the S-OFF, “brightness” pathways. The results revealed differences in the asymmetry between S-ON and S-OFF pathways dependent upon adapting field conditions that were expected to influence ipRGCs over other photoreceptors. In the second experiment, I used a modification of an S-cone contrast sensitivity task employing homochromatic “blue” sine-grating gabors of varying spatial frequencies to directly test ipRGC involvement in spatial pattern vision. The results from the second experiment showed a slight advantage to the perception of low spatial frequency gabors superimposed on chromatic adapting fields that were expected to influence ipRGCs more than the others. Preliminary evidence supporting a spatial tuning property of ipRGCs was also found. Overall, these findings suggest that ipRGCs have measurable influences on conscious, image-forming perceptions, and shed further light on the microcircuitry of the retinogeniculate pathway."-- from abstract.
Download or read book Webvision written by Helga Kolb and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Melanopsin Vision written by Daniel S. Joyce and published by Cambridge University Press. This book was released on 2023-01-31 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intrinsically photosensitive retinal ganglion cells (ipRGGs) are the most recently discovered photoreceptor class in the human retina. This Element integrates new knowledge and perspectives from visual neuroscience, psychology, sleep science and architecture to discuss how melanopsin-mediated ipRGC functions can be measured and their circuits manipulated. It reveals contemporary and emerging lighting technologies as powerful tools to set mind, brain and behaviour.
Download or read book Retinal Development written by Evelyne Sernagor and published by Cambridge University Press. This book was released on 2012-11-29 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: This advanced text, first published in 2006, takes a developmental approach to the presentation of our understanding of how vertebrates construct a retina. Written by experts in the field, each of the seventeen chapters covers a specific step in the process, focusing on the underlying molecular, cellular, and physiological mechanisms. There is also a special section on emerging technologies, including genomics, zebrafish genetics, and stem cell biology that are starting to yield important insights into retinal development. Primarily aimed at professionals, both biologists and clinicians working with the retina, this book provides a concise view of vertebrate retinal development. Since the retina is 'an approachable part of the brain', this book will also be attractive to all neuroscientists interested in development, as processes required to build this exquisitely organized system are ultimately relevant to all other parts of the central nervous system.
Download or read book Parallel Processing in the Visual System written by Jonathan Stone and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the mid-sixties, John Robson and Christina Enroth-Cugell, without realizing what they were doing, set off a virtual revolution in the study of the visual system. They were trying to apply the methods of linear systems analysis (which were already being used to describe the optics of the eye and the psychophysical performance of the human visual system) to the properties of retinal ganglion cells in the cat. Their idea was to stimulate the retina with patterns of stripes and to look at the way that the signals from the center and the antagonistic surround of the respective field of each ganglion cell (first described by Stephen Kuffier) interact to generate the cell's responses. Many of the ganglion cells behaved themselves very nicely and John and Christina got into the habit (they now say) of calling them I (interesting) cells. However. to their annoyance, the majority of neurons they recorded had nasty, nonlinear properties that couldn't be predicted on the basis of simple summ4tion of light within the center and the surround. These uncoop erative ganglion cells, which Enroth-Cugell and Robson at first called D (dull) cells, produced transient bursts of impulses every time the distribution of light falling on the receptive field was changed, even if the total light flux was unaltered.
Download or read book Pituitary Adenylate Cyclase Activating Polypeptide written by Hubert Vaudry and published by Springer Science & Business Media. This book was released on 2003 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pituitary Adenylate Cyclase-Activating Polypeptide is the first volume to be written on the neuropeptide PACAP. It covers all domains of PACAP from molecular and cellular aspects to physiological activities and promises for new therapeutic strategies. Pituitary Adenylate Cyclase-Activating Polypeptide is the twentieth volume published in the Endocrine Updates book series under the Series Editorship of Shlomo Melmed, MD.
Download or read book Advances in Photoreception written by National Research Council and published by National Academies Press. This book was released on 1990-02-01 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of a continuing series on Frontiers of Visual Science, this short volume contains papers presented at a recent symposium. These papers describe techniques for assessing the structure and function of photoreception, both in isolation and in aggregation as the "receptor mosaic" of the retina. Also described are dynamic and spatial sampling properties of photoreceptors, with an emphasis on techniques of measurement and associated models of retinal function. This volume should be of interest to basic vision scientists, clinical ophthalmologists, workers in human factors, and computer scientists curious about the visual apparatus of biological systems.
Download or read book Duplicity Theory of Vision written by Bjørn Stabell and published by Cambridge University Press. This book was released on 2009-08-13 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book chronicles the development of three classic theories within vision research, from the 17th century to today, focusing on duplicity theory.
Download or read book High Resolution Imaging in Microscopy and Ophthalmology written by Josef F. Bille and published by Springer. This book was released on 2019-08-13 with total page 411 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book provides a comprehensive overview of the application of the newest laser and microscope/ophthalmoscope technology in the field of high resolution imaging in microscopy and ophthalmology. Starting by describing High-Resolution 3D Light Microscopy with STED and RESOLFT, the book goes on to cover retinal and anterior segment imaging and image-guided treatment and also discusses the development of adaptive optics in vision science and ophthalmology. Using an interdisciplinary approach, the reader will learn about the latest developments and most up to date technology in the field and how these translate to a medical setting. High Resolution Imaging in Microscopy and Ophthalmology – New Frontiers in Biomedical Optics has been written by leading experts in the field and offers insights on engineering, biology, and medicine, thus being a valuable addition for scientists, engineers, and clinicians with technical and medical interest who would like to understand the equipment, the applications and the medical/biological background. Lastly, this book is dedicated to the memory of Dr. Gerhard Zinser, co-founder of Heidelberg Engineering GmbH, a scientist, a husband, a brother, a colleague, and a friend.
Download or read book Visual Transduction And Non Visual Light Perception written by Joyce Tombran-Tink and published by Springer Science & Business Media. This book was released on 2008-08-11 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reveals not only how the eye evolved into an organ of vision, but also describes how molecular mechanisms of key molecules operate in the phototransduction cascade. In this groundbreaking text, experts also explain mechanisms for sensing radiation outside of the visible wavelengths. Comprehensive and penetrating, the book brings together the mechanisms of the visual transduction cascade and is an invaluable text for everyone conducting research in the visual system.
Download or read book Pediatric Neuro Ophthalmology written by Michael C. Brodsky and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pediatric Neuroophthalmology details the diagnostic criteria, current concepts of pathogenesis, neuroradiological correlates, and clinical management of a large group of neuroophthalmic disorders that present in childhood. Surprisingly distinct from neuroophthalmic disorders afflicting adults, this set of diseases falls between the cracks of most ophthalmology training, and thus, warrants a practical, clinical guide for the practitioner in ophthalmology - the neuroophthalmologist, pediatric ophthalmologist, general ophthalmologist - as well as neurologists and for residents. The authors, leading pediatric ophthalmologists, have taken this difficult subject matter and developed an accessible, user-friendly manual with a detailed approach to the recognition, differential diagnosis, and management of pediatric neuroophthalmologic disorders.
Download or read book The Pupil Behavior Anatomy Physiology and Clinical Biomarkers written by Andrew J. Zele and published by Frontiers Media SA. This book was released on 2020-06-22 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.
Download or read book Encoding Visual Features by Parallel Ganglion Cell Initiated Pathways in the Healthy Diseased and Artificial Retina written by Béla Völgyi and published by Frontiers Media SA. This book was released on 2019-10-16 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photons are sensed by retinal photoreceptors whose matrix-like distribution underlies the transformation of illumination patterns of the visual scene into photoreceptor activity patterns in a visuotopic fashion. Activity of neighboring photoreceptors then are compared by secondary bipolar cells to decipher information regarding luminosity- and color-contrast. Bipolar cells achieve this by comparing signals received directly from their center receptive field with those come from spatially offset surrounding receptive field areas mediated by inhibitory, sign-inverting horizontal cells. This information is ultimately sent to retinal ganglion cells, the output neurons of the retina. In addition to the excitatory bipolar cell inputs, spatial and temporal features of ganglion cell activation are robustly modified by inner retinal amacrine cells through inhibitory chemical and/or excitatory electrical synaptic inputs. Ganglion cells sample various bipolar cell subtypes in their dendritic field and utilize collected inputs to generate a spike output code on luminosity-contrast, color-contrast, object motion, background motion, motion direction, changes in background illumination in a subtype specific manner. Ganglion cells in each subtype cover the retinal surface economically, thus collective information across the population provide a feature pattern and through time a feature movie to the brain. Some of these movies are utilized for image perception, whereas others are sent to accessory visual brain centers to control eye-movement, pupil contraction or circadian entrainment. A large body of information has been revealed in the past decade regarding this field, however much of the details still remain unknown or even enigmatic, including: (i) the precise description of neural circuits that serve each ganglion cell subtype to generate a specific feature movie; (ii) the estimation of the number of various ganglion cell subtypes that partake in image forming and non-image forming signaling towards the brain; (iii) the description of changes in the inputs, morphology and signaling of retinal ganglion cells when the tissue is under stress or undergoes disease related degenerative processes; (iv) the comparison of ganglion cell classes with those of the human retina and finally, (v) the practical use of all the above information to establish retina inspired visual algorithms to suit computer, drone and/or robotic vision. Therefore, research articles in this issue were collected to touch upon each of these topics and highlight recent advances of the related field.
Download or read book Anatomy Ocular physiology Biochemistry and genetics Pathology Microbiology Immunology Growth and senescence Optics Therapeutics Lasers and instrument technology Basic biostatistical and epidemiological terms written by Louise Bye and published by OUP Oxford. This book was released on 2013-05-23 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: An indispensable and fully comprehensive textbook, this covers the basic sciences in ophthalmology and is the only book you need to pass the FRCOphth Part 1 exam.
Download or read book The Neurobiology of Circadian Timing written by A. Kalsbeek and published by Elsevier. This book was released on 2012-09-21 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leading authors review the state-of-the-art in their field of investigation, and provide their views and perspectives for future research Chapters are extensively referenced to provide readers with a comprehensive list of resources on the topics covered All chapters include comprehensive background information and are written in a clear form that is also accessible to the non-specialist Leading authors review the state-of-the-art in their field of investigation, and provide their views and perspectives for future research Chapters are extensively referenced to provide readers with a comprehensive list of resources on the topics covered All chapters include comprehensive background information and are written in a clear form that is also accessible to the non-specialist
Download or read book Encyclopedia of Sleep written by and published by Academic Press. This book was released on 2013-01-17 with total page 2626 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a world of 24-hour media saturation, sleep has become an increasingly fraught enterprise. The award-winning four-volume Encyclopedia of Sleep, Four Volume Set is the largest reference, either online or in print, on the subject of sleep. Written to be useful for the novice and the established researcher and clinician, Topic areas will include sleep across the life cycle and in other species, sleep and women, sleep and the elderly, pediatric sleep, sleep deprivation and loss, sleep mechanisms, sleep physiology and pathophysiology, sleep disorders, neurobiology, chronobiology, pharmacology, and impact of other disorders on sleep. Recognizing the many fields that are connected to sleep science, the editorial team has been carefully chosen to do justice to this highly interdisciplinary field of study. The steady growth of researchers and clinicians in the sleep field attests to the continued interest in the scientific study of sleep and the management of patients with sleep disorders, and anyone involved in this exciting field should find this work to be an invaluable reference. 2013 PROSE Award winner for Multivolume Reference in Science from the Association of American Publishers Thoroughly interdisciplinary: looks at sleep throughout the life cycle, with exceptional coverage of basic sleep concepts, the physiology of sleep as well as sleep disorders of all descriptions Excellent coverage of sleep and special populations, covering the lifespan, as well as gender and ethnic differences, among others Chapters focusing on sleep disorders are grouped under the broad categories classified in the ICSD-2 for clear organization so that the reader can effectively access the steps involved in diagnosing and treating these disorders Online version is linked both within the encyclopedia (to related content) and to external sources (such as primary journal content) so that users have easy access to more detailed information if needed
Download or read book Translation and Processing of Light by the Non Image Forming Visual System Context Mechanisms and Applications written by Fabian-Xosé Fernandez and published by Frontiers Media SA. This book was released on 2021-10-18 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt:
