All the different parts of your eyes work together to help you see. First, light passes through the cornea (the clear front layer of the eye). The cornea is shaped like a dome and bends light to help the eye focus. Some of this light enters the eye through an opening called the pupil
(PYOO-pul). The iris (the colored part of the eye) controls how much light the pupil lets in. Next, light passes through the lens (a clear inner part of the eye). The lens works together with the cornea to focus light correctly on the retina. When light hits the retina (a light-sensitive layer of tissue at the back of the eye), special cells called photoreceptors turn the light into electrical
signals. These electrical signals travel from the retina through the optic nerve to the brain. Then the brain turns the signals into the images you see. Your eyes also need tears to work correctly.
 Last updated: April 20, 2022 Table 28.1. Normalized values of volume conductor parameters of the model of the eye
namely, Laplace's equation subject to the following boundary conditions: At all passive interfaces between regions of different conductivity the normal component of current density is continuous and the electric potential is continuous. For the retinal double layer, the normal component of current density is continuous, but the potential is discontinuous across this source by a value equal to the double layer strength (expressed in volts). Finally, for the R-membrane, the current density is also continuous, but there is a discontinuity in potential; this is given by the product of membrane impedance (Ωcm�) and the normal component of current density. Doslak, Plonsey, and Thomas (1980) solved this by locating a system of nodal points over the entire region and then using the method of finite differences and overrelaxation. Mathematical details are contained in Doslak, Plonsey, and Thomas (1982). The model was used by Doslak and Hsu (1984) to study the effect of blood in the vitreous humor on the ERG magnitude. They were able to establish that little effect on ERG magnitude could be expected from this condition. REFERENCESdu Bois-Reymond EH (1848): Untersuchungen Ueber Thierische Elektricit�t, Vol. 1, 56+743 pp. G Reimer, Berlin. Carpenter RHS (1988): Movements of the Eyes, 2nd ed., 593 pp. Pion, London. Charles S (1979): Electrical signals of the retinal microcircuitry. In Physiology of the Human Eye and Visual System, ed. RE Records, pp. 319-27, Harper & Row, Hagerstown. Clark JW (1978): The electroretinogram. In Medical Instrumentation, ed. JG Webster, pp. 177-84, Houghton Mifflin, Boston. Dewar J, McKendrick JG (1873): On the physiological action of light. Proc. Roy. Soc. (Edinburgh) 8: 179-82. Doslak MJ (1988): Electroretinography. In Encyclopedia of Medical Devices and Instrumentation, Vol. 2, ed. JG Webster, pp. 1168-80, John Wiley, New York. Doslak MJ, Hsu P-C (1984): Application of a bioelectric field model of the ERG to the effect of vitreous haemorrhage. Med. & Biol. Eng. & Comput. 22: 552-7. Doslak MJ, Plonsey R, Thomas CW (1980): The effects of variations of the conducting media inhomogeneities on the electroretinogram. IEEE Trans. Biomed. Eng. 27: 88-94. Doslak MJ, Plonsey R, Thomas CW (1982): Numerical solution of the bioelectric field. Med. & Biol. Eng. & Comput. 19: 149-56. Granit R (1955): Receptors and Sensory Perception, 369 pp. Yale University Press, New Haven. Holmgren F (1865): Method att objectivera effecten af ljusintryck p� retina. Uppsala L�k. F�r. F�rh. 1: 184-98. Levick WR, Dvorak DR (1986): The retina - From molecules to networks. Trends Neurosci. 9: 181-5. Oster PJ, Stern JA (1980): Electro-oculography. In Techniques in Psychophysiology, ed. I Martin, PH Venables, pp. 276-97, John Wiley, New York. Rahko T, Karma P, Torikka T, Malmivuo JA (1980): Microprocessor-based four-channel electronystagmography system. Med. & Biol. Eng. & Comput. 18:(1) 104-8. Rodieck RW (1973): The Vertebrate Retina, 1044 pp. Freeman, San Francisco. Stockwell CW (1988): Nystagmography. In Encyclopedia of Medical Devices and Instrumentation, Vol. 3, ed. JG Webster, pp. 2090-4, John Wiley, New York. Wiesel TN, Brown KT (1961): Localization of origins of electroretinogram components by intraretinal recording in the intact cat eye. J. Physiol. (Lond.) 158: 257-80. Young LR, Sheena D (1975): Eye movement measurement techniques. Amer. Physiologist 30: 315-30. (Reprinted in: Encyclopedia of Medical Devices and Instrumentation, Webster, JG, ed., J. Wiley & Sons, New York, vol. 2., pp. 1259-1269, 1988). Young LR, Sheena D (1988): Eye-movement measurement techniques. In Encyclopedia of Medical Devices and Instrumentation, ed. JG Webster, pp. 1259-69, John Wiley, New York. FURTHER READINGBerthoz A, Melvill Jones G (1985): Adaptive mechanisms in gaze control. In Reviews of Oculomotor Research, Vol. 1, ed. DA Robinson, H Collewjin, p. 386, Elsevier, Amsterdam. B�ttner-Ennever JA (1989): Neuroanatomy of the oculomotor system. In Reviews of Oculomotor Research, Vol. 2, ed. DA Robinson, H Collewjin, p. 478, Elsevier, Amsterdam. Kowler E (1990): Eye movements and their role in visual and cognitive processes. In Reviews of Oculomotor Research, Vol. 4, ed. DA Robinson, H Collewjin, p. 496, Elsevier, Amsterdam. Wurtz RH, Goldberg ME (1989): The neurobiology of saccadic eye movements. In Reviews of Oculomotor Research, Vol. 3, ed. DA Robinson, H Collewjin, Elsevier, Amsterdam.
What part of the eye converts visual images to electrical impulses?The retina is the light-sensitive tissue at the back of the eye. The retina instantly converts light, or an image, into electrical impulses. The retina then sends these impulses, or nerve signals, to the brain.
What is responsible for converting an image into an electrical impulse?Photoreceptors are specialized neurons found in the retina that convert light into electrical signals that stimulate physiological processes. Signals from the photoreceptors are sent through the optic nerve to the brain for processing.
What converts light into nerve impulses in the eye?The sensory cells receive these light signals and convert them to nerve signals. The retina has two kinds of sensory cells, called cones and rods.
Which part of the eyes is responsible for turning an image into a collection of signals the brain can interpret?The lens focuses light through the vitreous humor, a clear gel-like substance that fills the back of the eye and supports the retina. The retina receives the image that the cornea focuses through the eye's internal lens and transforms this image into electrical impulses that are carried by the optic nerve to the brain.
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What part of the eye is responsible for converting an image into an electrical impulse?
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