Open Issues in the Study of Human Retina
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TETRACHROMATIC COLOR VISION Kimberly A. Jameson Prepared For
TETRACHROMATIC COLOR VISION Kimberly A. Jameson prepared for The Oxford Companion to Consciousness. Wilken, P., Bayne, T. & Cleeremans, A. (Ed.s). Oxford University Press: Oxford. To appear in 2007. The term“tetrachromacy” describes the physiological possession of four different classes of simultaneously functioning retinal photopigments (also called “weak tetrachromacy”). From an empirical standpoint, tetrachromatic color vision (or “strong tetrachromacy”) additionally requires demonstrating that mixtures of four independent appropriately chosen primary lights will simulate all distinc- tions in appearance possible in visible color space. Independence of the primary lights implies that no mixtures of any subset of these lights (or their intensity variants) will produce an identical match to any combination of mixtures of the remaining lights. By comparison, trichromacy empirically requires only three primaries to simulate all visible colors. Established theory states that normal color vision humans are trichromats (as, primarily, are Old World monkeys and apes). The first element of trichro- macy is the output from three simultaneously functioning retinal cone classes: Short-, Medium-, and Long- Wavelenth Sensitive (SWS, MWS, & LWS) cones. Three cone classes alone do not establish a trichromat color code, however. A postreceptoral code for three categories of signal is also needed. A standard vision science assumption is that the postreceptoral recoding of cone outputs initiates the neural trivariant (or trichromatic) property of human color percep- tion, and the need for only three primary lights to match any test light. ANIMAL TETRACHROMACY: Tetrachromacy is an early vertebrate characteristic, existing in fish and reptiles, and is evolutionarily more ancient than primate trichromacy. Essentially all diu- ral birds have four retinal cone types (two SWS classes, plus a MWS and a LWS class) which neurally produce four dimensional color experience, or tetrachro- matic color vision. -
Color Vision Test for Dichromatic and Trichromatic Macaque Monkeys
Journal of Vision (2013) 13(13):1, 1–15 http://www.journalofvision.org/content/13/13/1 1 Color vision test for dichromatic and trichromatic macaque monkeys National Institute for Physiological Sciences, Okazaki, Aichi, Japan Electronics-Inspired Interdisciplinary Research Institute, Toyohashi University of Technology, Toyohashi, Aichi, # Kowa Koida* Japan $ National Institute for Physiological Sciences, Okazaki, Aichi, Japan University for Advanced Studies (SOKENDAI), Okazaki, # Isao Yokoi* Aichi, Japan $ National Institute for Physiological Sciences, Okazaki, Aichi, Japan University for Advanced Studies (SOKENDAI), Okazaki, # Gouki Okazawa Aichi, Japan $ Faculty of Rehabilitation, Chubu Gakuin University, Seki, # Akichika Mikami Gifu, Japan $ Department of Biology, Bogor Agricultural University, # Kanthi Arum Widayati Bogor, Indonesia $ Primate Research Institute, Kyoto University, Inuyama, # Shigehiro Miyachi Aichi, Japan $ National Institute for Physiological Sciences, Okazaki, Aichi, Japan University for Advanced Studies (SOKENDAI), Okazaki, # Hidehiko Komatsu Aichi, Japan $ Dichromacy is a color vision defect in which one of the identified dichromatic macaques (Macaca fascicularis) three cone photoreceptors is absent. Individuals with with that of normal trichromatic macaques. In the color dichromacy are called dichromats (or sometimes ‘‘color- discrimination test, dichromats could not discriminate blind’’), and their color discrimination performance has colors along the protanopic confusion line, though contributed significantly -
Human Trichromacy Revisited PNAS PLUS
Human trichromacy revisited PNAS PLUS Hiroshi Horiguchia,b,1, Jonathan Winawera, Robert F. Doughertyc, and Brian A. Wandella,c aPsychology Department, Stanford University, Stanford, CA 94305; bDepartment of Ophthalmology, School of Medicine, Jikei University, Tokyo 105-8461, Japan; and cStanford Center for Cognitive and Neurobiological Imaging, Stanford, CA 94305 AUTHOR SUMMARY The history of trichromatic color As predicted by the classic tri- theory spans nearly 300 y, be- msARC Fovea Periphery chromatic model, subjects fail to ’ Opticks (%) ginning with Newton s 10 see cone-silent stimuli presented (1). Thomas Young’s Royal So- Visible in the fovea. In contrast, subjects Not ciety Lecture (2) explained how 0 Not do see cone-silent stimuli pre- Visible Visible Visible Visible color perception is initiated by S1 sented to the peripheral visual S2 fi the absorption of light in three Cone-silent −10 eld. In extensive computational S3 fi types of human light receptors, −10 0 10 −10 0 10 (%) modeling, we could nd no plau- the cones. The theory of tri- S-cone S-cone sible pigment density adjustment chromacy is the foundation of (including the lens or photopig- modern color technologies (3). Fig. P1. Built and found. (A) An apparatus using six primary lights was ment densities) that explains the built for the experiment. Mean luminance through the eyepiece was measurements in the periphery For more than a century, the 2 absorption of light in the retina 2,060 cd/m .(B) Graphs represent detection thresholds for stimuli that based on a model that includes was thought to occur only in the have some S-cone contrast and cone-silent contrast, but no L- or M- only three cone photopigments. -
PARS PLANA VITRECTOMY, RIGHT EYE a Case Study on the Operating
PARS PLANA VITRECTOMY, RIGHT EYE A Case Study on the Operating Room Presented to The Faculty of School of Nursing University of Baguio In Partial fulfillment of the Requirement for the Subject NCENL06 SUBMITTED TO: Larry Michelle Pascual, RN Clinical Instructor SUBMITTED BY: Arlene Esilen Carreon September 2012 1 ACKNOWLEDGMENT I owe my deepest gratitude to the following for the making of this case possible: First and foremost to our Creator, as source of our life and being, and for reasons too numerous to mention; To the University of Baguio, for being true to its mission and vision of empowering its students, giving us the chance to develop our skills through experience; To the Dean, Ms. Jocelyn Apalla, Department Head, Ms. Helen Alalag, and BSN IV Coordinator, Ms. Minda Bahug for making hospital exposure feasible; To my clinical instructor, Mr. Larry Michelle Pascual, who’s intellectual, clinical and practical insights and guidance made our hospital duty experience appreciated and valued in all dimensions; To my parents, for their unending love and support, and for molding me to become the person that I am right now, for the encouragement and words of wisdom they have inculcated in my mind, and the lessons they have taught that help me go on in this part of my journey in life, my deepest gratitude. 2 TABLE OF CONTENTS Chapter Page Title page........................................... i Acknowledgement...................................... ii Table of Content .................................... iii Chapter I Patient’s Profile............................... 1 a. Biographic Data Chapter II Anatomy and Physiology.............................. 2 a. Structure of the Human Eye Chapter III Pathophysiology...................................... 15 Chapter IV Patient’s Preparation............................... -
Colour Vision Deficiency
Eye (2010) 24, 747–755 & 2010 Macmillan Publishers Limited All rights reserved 0950-222X/10 $32.00 www.nature.com/eye Colour vision MP Simunovic REVIEW deficiency Abstract effective "treatment" of colour vision deficiency: whilst it has been suggested that tinted lenses Colour vision deficiency is one of the could offer a means of enabling those with commonest disorders of vision and can be colour vision deficiency to make spectral divided into congenital and acquired forms. discriminations that would normally elude Congenital colour vision deficiency affects as them, clinical trials of such lenses have been many as 8% of males and 0.5% of femalesFthe largely disappointing. Recent developments in difference in prevalence reflects the fact that molecular genetics have enabled us to not only the commonest forms of congenital colour understand more completely the genetic basis of vision deficiency are inherited in an X-linked colour vision deficiency, they have opened the recessive manner. Until relatively recently, our possibility of gene therapy. The application of understanding of the pathophysiological basis gene therapy to animal models of colour vision of colour vision deficiency largely rested on deficiency has shown dramatic results; behavioural data; however, modern molecular furthermore, it has provided interesting insights genetic techniques have helped to elucidate its into the plasticity of the visual system with mechanisms. respect to extracting information about the The current management of congenital spectral composition of the visual scene. colour vision deficiency lies chiefly in appropriate counselling (including career counselling). Although visual aids may Materials and methods be of benefit to those with colour vision deficiency when performing certain tasks, the This article was prepared by performing a evidence suggests that they do not enable primary search of Pubmed for articles on wearers to obtain normal colour ‘colo(u)r vision deficiency’ and ‘colo(u)r discrimination. -
組織學 Histology 台北醫學大學/解剖學科 教授:邱瑞珍 分機號碼:3261 電子郵件信箱:[email protected]
組織學 Histology 台北醫學大學/解剖學科 教授:邱瑞珍 分機號碼:3261 電子郵件信箱:[email protected] 1 Special sense – eye 台北醫學大學/解剖學科 馮琮涵 副教授 分機3250 E-mail: [email protected] 2 學習目的 •希望同學知道視網膜之顯微構造 •希望同學知道眼瞼顯微結構 3 參考資料 • Junqueira's Basic Histology, twelfth edition, text and atlas, Anthony L. Mescher, McGraw-Hill Companies 4 Summary • A) eye ball: – tunica fibrosa – cornea and sclera – tunica vasculosa—choroids, ciliary process, iris – tunica interna—retina – Lens – vitrous body • B) accessory structure: – eyelids – lacrimal gland 5 6 7 8 Eye • Wall of eyeball: tunicatunica fibrosafibrosa – cornea and sclera tunicatunica vasculosavasculosa – choroid, ciliary body & iris tunicatunica nervosanervosa – retina & pigmented layer opticoptic nervenerve & oraora serrataserrata • Contents: lens, aqueous humor & vitreous body 9 10 Cornea cornea – transparent, avascular, sensory innervation (CN V1) •• cornealcorneal epitheliumepithelium : non-cornified stratified squamous epi. •• BowmanBowman’’ss membranemembrane : basement membrane •• stromastroma : laminated collagen fibers; muco-polysaccharide matrix •• DescemetDescemet’’ss membranemembrane: basement membrane • endothelium 11 Cornea 12 Sclera sclera – thick c.t. with parallel collagen fibers, insertion site of extrinsic eye muscles • Epi-scleral tissue: loose vascular c.t., attaches conjunctiva • stroma: parallel collagen fibers Corneo-scleral junction (limbus): • trabecular meshwork, • canal of Schlemm (scleral venous sinus) 13 14 trabecular meshwork 15 Choroid choroid – soft and thin c.t. membrane • Supra-choroid layer : -
Lecture 4 Colour Perception
Lecture 4 What does color do for us? Colour Perception • The world of color is a world of yellow daffodils, painted window shutters, orange-red sunsets. We pick favourite colours and react emotionally to color (purple with rage, green with envy). • Few mammals except primates have colour vision, so other than creating aesthetic appearance and mood what does it do for us? • The images on the right suggest that evolution of color vision was probably related to the advantages it provides in finding food. What is colour? Why does the sky look blue? • One way to interpret Newton’s result is that the perception of • In his room at Cambridge color occurs when some University, Isaac Newton wavelengths are subtracted from placed a prism so that white light. sunlight shining through a hole in the shutter of his • This occurs naturally when light window entered the prism. from the sun is scattered by particles of air in the atmosphereto • He discovered that the prism create the perception of blue sky split the sunlight into a and yellow sun. spectrum of colours. • Short wavelenght light (blue) is • The visible spectrum ranges scattered more than long from 400 nm (violet) to 700 wavelength light (red). This effect nm (red). becomes most pronounced when the light has to travel further (sunset) Why are objects the color they are? Mixing paint versus mixing colour • The colour of an object depends on • The artist can never perfectly wavelengths contained in the duplicate the effects of light incident light and which of these because pigments and light do wavelengths it reflects. -
Phylogenetic Analyses Suggest Independent Origins for Trichromatic Color Vision in Apes and Old World Monkeys
bioRxiv preprint doi: https://doi.org/10.1101/2020.03.23.003855; this version posted March 23, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Phylogenetic analyses suggest independent origins for trichromatic color vision in apes and Old World monkeys Jessica Toloza-Villalobos1 & Juan C. Opazo1 ,2 1Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile. 2Millennium Nucleus of Ion Channels-associated Diseases (MiNICAD). Corresponding authors: Jessica Toloza-Villalobos ([email protected]) Juan C. Opazo ([email protected]) Phone: +56 63 2221674 Running title: Keywords: trichromatic color vision, opsin gene, gene duplication, primate color vision bioRxiv preprint doi: https://doi.org/10.1101/2020.03.23.003855; this version posted March 23, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Abstract In catarrhine primates, trichromatic color vision is associated with the presence of three opsin genes that absorb light at three different wavelengths. The OPN1LW and OPN1MW genes are found on the X chromosome. Their proximity and similarity suggest that they originated from a duplication event in the catarrhine ancestor. In this study we use the primate genomes available in public databases to study the duplicative history of the OPN1LW and OPN1MW genes and characterize their spectral sensitivity. Our results reveal a phylogenetic tree that shows a clade containing all X-linked opsin paralogs found in Old World monkeys to be related to a clade containing all X-linked opsin paralogs identified in apes, suggesting that routine trichromacy originated independently in apes and Old World monkeys. -
Chapter 7: Perceiving Color
Chapter 7: Perceiving Color -The physical dimensions of color -The psychological dimensions of color appearance (hue, saturation, brightness) -The relationship between the psychological and physical dimensions of color (Trichromacy Color opponency) - Other influences on color perception (color constancy, top-down effects) Sir Isaac Newton Newton’s Prism Experiment (1704) White light is composed of multiple colors Light Monochromatic light : one wavelength (like a laser) Physical parameters for monochromatic light 1. Wavelength 2. Intensity Heterochromatic light : many wavelengths (normal light sources) For heterochromatic light The spectral composition gives the intensity at each wavelength Monochromatic light Heterochromatic light Spectral composition of two common (heterochromatic) illuminants The spectral components of light entering the eye is the product of the illuminant and the surface reflectance of objects. Reflectance of some common surfaces and pigments 350 400 450 500 550 600 650 700 750 800 Surface reflectance of some common objects 350 400 450 500 550 600 650 700 750 800 Spectral composition of light entering the eye after being reflected from a surface = Spectral composition of the Reflectance of the surface illuminant X Consider a ripe orange illuminated with a bright monochromatic blue (420 nm) light. What color will the banana appear to be? a. bright orange b. dark/dim orange Blue (monochromatic) c. black d. dark/dim blue Relative amount of light of amount Relative Wavelength Spectral composition of light entering the -
Color, Pattern, and the Retinal Cone Mosaic
Available online at www.sciencedirect.com ScienceDirect Color, pattern, and the retinal cone mosaic David H Brainard Textbook trichromacy accounts for human color vision in terms [e.g. the colors on televisions and computer displays of spectral sampling by three classes of cone photoreceptors. are produced by mixtures of red, green and blue pri- This account neglects entangling of color and pattern maries, rather than be recreating the actual spectra we information created by wavelength-dependent optical blur encounter in daily viewing; 2]. (chromatic aberrations) and interleaved spatial sampling of the retinal image by the three classes of cones. Recent Although the textbook account is deep and correct, it also experimental, computational, and neurophysiological work is embodies an important simplification. In particular, it now considering color and pattern vision at the elementary encourages the view that color vision may be understood scale of daylight vison, that is at the scale of individual cones. without consideration of the spatial pattern of the images The results provide insight about rich interactions between that reach the retina, that is, that color vision and pattern color and pattern vision as well as the role of the statistical vision are in some sense independent processes. Under structure of natural scenes in shaping visual processing. this view, it would be appropriate to study color vision for spatially uniform patches and pattern vision for grayscale Address (luminance) images, with any interactions between the Department of Psychology, University of Pennsylvania, Philadelphia, PA, two relegated as effects of interest only to specialists. 19104, United States Although there is no denying that we have learned much Corresponding author: Brainard, David H ([email protected]) about both color and pattern vision through separate consideration of the two, there is also no doubt that there can be large and striking interactions between color and Current Opinion in Behavioral Sciences 2019, 30:41–47 pattern vision (Figure 2). -
Human Trichromacy Revisited
Human trichromacy revisited Hiroshi Horiguchia,b,1, Jonathan Winawera, Robert F. Doughertyc, and Brian A. Wandella,c aPsychology Department, Stanford University, Stanford, CA 94305; bDepartment of Ophthalmology, School of Medicine, Jikei University, Tokyo 105-8461, Japan; and cStanford Center for Cognitive and Neurobiological Imaging, Stanford, CA 94305 Edited by Thomas D. Albright, The Salk Institute for Biological Studies, La Jolla, CA, and approved November 15, 2012 (received for review August 20, 2012) The presence of a photopigment (melanopsin) within certain reti- passing through the cornea, lens, and inert pigments of the eye. nal ganglion cells was a surprising and significant discovery. This Individual variability in the transmission through these structures pigment is routinely described as “nonvisual” to highlight its signal- makes it impossible to specify a light that is absorbed uniquely by ing role in pupil dilation and circadian rhythms. Here we asked melanopsin and not the cones; achieving this control with sufficient whether light absorbed by melanopsin can be seen by healthy hu- precision to convince a skeptical reviewer or ourselves is unlikely. man subjects. To answer this requires delivering intense (above rod Hence, we used a different approach. We measured contrast saturation), well-controlled lights using four independent primaries. thresholds along many directions in the four-dimensional space We collected detection thresholds to many four-primary stimuli. specified by the four primary lights. If visibility depends on the Threshold measurements in the fovea are explained by trichromatic photons captured by three photopigments, there must be a com- theory, with no need to invoke a fourth photopigment. In the pe- bination of increments and decrements of the four primaries riphery, where melanopsin is present, threshold measurements de- that is invisible. -
Human Trichromacy Revisited PNAS PLUS
Human trichromacy revisited PNAS PLUS Hiroshi Horiguchia,b,1, Jonathan Winawera, Robert F. Doughertyc, and Brian A. Wandella,c aPsychology Department, Stanford University, Stanford, CA 94305; bDepartment of Ophthalmology, School of Medicine, Jikei University, Tokyo 105-8461, Japan; and cStanford Center for Cognitive and Neurobiological Imaging, Stanford, CA 94305 AUTHOR SUMMARY The history of trichromatic color As predicted by the classic tri- theory spans nearly 300 y, be- msARC Fovea Periphery chromatic model, subjects fail to ’ Opticks (%) ginning with Newton s 10 see cone-silent stimuli presented (1). Thomas Young’s Royal So- Visible in the fovea. In contrast, subjects Not ciety Lecture (2) explained how 0 Not do see cone-silent stimuli pre- Visible Visible Visible Visible color perception is initiated by S1 sented to the peripheral visual S2 fi the absorption of light in three Cone-silent −10 eld. In extensive computational S3 fi types of human light receptors, −10 0 10 −10 0 10 (%) modeling, we could nd no plau- the cones. The theory of tri- S-cone S-cone sible pigment density adjustment chromacy is the foundation of (including the lens or photopig- modern color technologies (3). Fig. P1. Built and found. (A) An apparatus using six primary lights was ment densities) that explains the built for the experiment. Mean luminance through the eyepiece was measurements in the periphery For more than a century, the 2 absorption of light in the retina 2,060 cd/m .(B) Graphs represent detection thresholds for stimuli that based on a model that includes was thought to occur only in the have some S-cone contrast and cone-silent contrast, but no L- or M- only three cone photopigments.