Photoreceptor cells responsible for color vision made to function in bright light
Cone cells
Normalized responsivity spectra of human cone cells, S, M, and L types
Details
Location
Retina of vertebrates
Function
Color vision
Identifiers
MeSH
D017949
NeuroLex ID
sao1103104164
TH
H3.11.08.3.01046
FMA
67748
Anatomical terms of neuroanatomy
[edit on Wikidata]
Cone cells or cones are photoreceptor cells in the retinas of vertebrates' eyes. They respond differently to light of different wavelengths, and the combination of their responses is responsible for color vision. Cones function best in relatively bright light, called the photopic region, as opposed to rod cells, which work better in dim light, or the scotopic region. Cone cells are densely packed in the fovea centralis, a 0.3 mm diameter rod-free area with very thin, densely packed cones which quickly reduce in number towards the periphery of the retina. Conversely, they are absent from the optic disc, contributing to the blind spot. There are about six to seven million cones in a human eye (vs ~92 million rods), with the highest concentration being towards the macula.[1]
Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color. They are also able to perceive finer detail and more rapid changes in images because their response times to stimuli are faster than those of rods.[2] Cones are normally one of three types: S-cones, M-cones and L-cones. Each type expresses a different opsin: OPN1SW, OPN1MW, and OPN1LW, respectively. These cones are sensitive to visible wavelengths of light that correspond to short-wavelength, medium-wavelength and longer-wavelength light respectively.[3] Because humans usually have three kinds of cones with different photopsins, which have different response curves and thus respond to variation in color in different ways, humans have trichromatic vision. Being color blind can change this, and there have been some verified reports of people with four types of cones, giving them tetrachromatic vision.[4][5][6]
The three pigments responsible for detecting light have been shown to vary in their exact chemical composition due to genetic mutation; different individuals will have cones with different color sensitivity.
^"The Rods and Cones of the Human Eye". HyperPhysics Concepts - Georgia State University.
^Kandel, E.R.; Schwartz, J.H; Jessell, T. M. (2000). Principles of Neural Science (4th ed.). New York: McGraw-Hill. pp. 507–513. ISBN 9780838577011.
^Schacter, Gilbert, Wegner, "Psychology", New York: Worth Publishers,2009.
^
Jameson, K. A.; Highnote, S. M. & Wasserman, L. M. (2001). "Richer color experience in observers with multiple photopigment opsin genes" (PDF). Psychonomic Bulletin and Review. 8 (2): 244–261. doi:10.3758/BF03196159. PMID 11495112. S2CID 2389566.
^"You won't believe your eyes: The mysteries of sight revealed". The Independent. 7 March 2007. Archived from the original on 6 July 2008. Retrieved 22 August 2009. Equipped with four receptors instead of three, Mrs M - an English social worker, and the first known human "tetrachromat" - sees rare subtleties of colour.
^Mark Roth (September 13, 2006). "Some women may see 100,000,000 colors, thanks to their genes". Pittsburgh Post-Gazette. Archived from the original on November 8, 2006. Retrieved August 22, 2009. A tetrachromat is a woman who can see four distinct ranges of color, instead of the three that most of us live with.
Conecells or cones are photoreceptor cells in the retinas of vertebrates' eyes. They respond differently to light of different wavelengths, and the combination...
mammalian eyes: rods, cones, and intrinsically photosensitive retinal ganglion cells. The two classic photoreceptor cells are rods and cones, each contributing...
channels for conveying color information, or possessing four types of conecell in the eye. Organisms with tetrachromacy are called tetrachromats. In...
Rod cells are photoreceptor cells in the retina of the eye that can function in lower light better than the other type of visual photoreceptor, cone cells...
up: Perception of color begins with specialized retinal cells known as conecells. Conecells contain different forms of opsin – a pigment protein – that...
As a part of the retina, bipolar cells exist between photoreceptors (rod cells and conecells) and ganglion cells. They act, directly or indirectly, to...
light spectrum with three types of conecells (trichromacy). Other animals may have a different number of conecell types or have eyes sensitive to different...
many other animals, photopic vision allows color perception, mediated by conecells, and a significantly higher visual acuity and temporal resolution than...
in the conecell cyclic nucleotide-gated ion channels CNGA3 (ACHM2) and CNGB3 (ACHM3), the conecell transducin, GNAT2 (ACHM4), subunits of cone phosphodiesterase...
conveying color information, derived from the three different types of conecells in the eye. Organisms with trichromacy are called trichromats. The normal...
belt, where the ganglion cell layer is composed of more than five layers of cells, as well as the highest density of cones; the perifovea is the outermost...
about color by processing signals from cone and rod cells in an antagonistic manner. The three types of conecells have some overlap in the wavelengths...
are characterised by initial loss of rod photoreceptor cell function followed by that of the cones and for this reason night blindness is the first significant...
the eye reports input from short wave blue conecells along with a sub-sensitivity of the long wave cones which respond secondarily to that same deep...
distribution of receptor cells across the retina is different between the two main types, rod cells and conecells. Rod cells are unable to distinguish...
third class of photoreceptors, in addition to rod and conecells. Compared to the rods and cones, the ipRGCs respond more sluggishly and signal the presence...
may imply that they have been modified from a conecell ancestor. They occasionally occur in double cones/double rods. Some oil droplets are coloured,...
variation in the functionality of one or more of the three classes of conecells in the retina, which mediate color vision. The most common form is caused...
CIELUV color space. The human eye with normal vision has three kinds of conecells that sense light, having peaks of spectral sensitivity in short ("S",...
viability factor, RdCVF) that protects the conecells from apoptosis (cell death). However, when the rod cells die, this substance is no longer provided...
A cone dystrophy is an inherited ocular disorder characterized by the loss of conecells, the photoreceptors responsible for both central and color vision...
pigmented epithelial cells. The primary light-sensing cells in the retina are the photoreceptor cells, which are of two types: rods and cones. Rods function...
amacrine cells synapse with retinal ganglion cells. The synapses in the outer plexiform layer are between the rod cell endings or conecell branched foot...
sight'. In the human eye, conecells are nonfunctional in low visible light. Scotopic vision is produced exclusively through rod cells, which are most sensitive...
is the state of having two types of functioning photoreceptors, called conecells, in the eyes. Organisms with dichromacy are called dichromats. Dichromats...
of cones, rather than each type of cone's individual response.[citation needed][dubious – discuss] Color blindness can be classified by the conecell that...
mediate vision in vertebrates. They include the opsins in human rod and conecells. They are often abbreviated to opsin, as they were the first opsins discovered...
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