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Encyclopedia > Receptive field

The receptive field of a sensory neuron is a region of space in which the presence of a stimulus will alter the firing of that neuron. Receptive fields have been identified for neurons of the auditory system, the somatosensory system, and the visual system. Drawing by Santiago Ramón y Cajal of neurons in the pigeon cerebellum. ... In physiology, a stimulus is a detectable change in the internal or external environment. ... The auditory system is the sensory system for the sense of hearing. ... The somatosensory system is the sensory system of somatic sensation. ... The visual system is the part of the nervous system which allows organisms to see. ...


The concept of receptive fields can be extended to further up the neural system; if many sensory receptors all form synapses with a single cell further up, they collectively form the receptive field of that cell. For example, the receptive field of a ganglion cell in the retina of the eye is composed of input from all of the cone cells which synapse with it, and a group of ganglion cells in turn forms the receptive field for a cell in the brain. This process is called convergence. Synapses allow nerve cells to communicate with one another through axons and dendrites, converting electrical signals into chemical ones. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ... A ganglion cell (or sometimes called a gangliocyte) is a type of neuron located in the retina that receives visual information from photoreceptors via various intermediate cells such as bipolar cells, amacrine cells, and horizontal cells. ... Human eye cross-sectional view. ... A human eye. ... Normalised absorption spectra of human cone (S,M,L) and rod (R) cells Cone cells, or cones, are cells in the retina of the eye which only function in relatively bright light. ... In the absence of a more specific context, convergence denotes the approach toward a definite value, as time goes on; or to a definite point, a common view or opinion, or toward a fixed or equilibrium state. ...

Contents

Auditory system

In the auditory system, receptive fields can be volumes in auditory space, or can be regions of auditory frequencies. Researchers rarely equate auditory receptive fields to particular regions of the sensory epithelium such as, in the case of mammals, hair cells in the cochlea. Sine waves of various frequencies; the bottom waves have higher frequencies than those above. ... Orders Subclass Monotremata Monotremata Subclass Marsupialia Didelphimorphia Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemorphia Diprotodontia Subclass Placentalia Xenarthra Dermoptera Desmostylia Scandentia Primates Rodentia Lagomorpha Insectivora Chiroptera Pholidota Carnivora Perissodactyla Artiodactyla Cetacea Afrosoricida Macroscelidea Tubulidentata Hyracoidea Proboscidea Sirenia The mammals are the class of vertebrate animals primarily characterized by the presence of mammary... Hair cells are the sensory cells of both the auditory system and the vestibular system in all vertebrates. ... The cochlea is the auditory branch of the inner ear. ...


Somatosensory system

In the somatosensory system, receptive fields are regions of the skin or of internal organs. Some types of mechanoreceptors have large receptive fields, while others have smaller ones. It has been suggested that this article or section be merged with Epidermis (skin). ... In biology, an organ is a group of tissues which perform some function. ... A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. ...


Large receptive fields allow the cell to detect changes over a wider area, but lead to a less precise perception. Thus, the fingers, which require the ability to detect fine detail, have many, densely packed mechanoreceptors with small receptive fields, while the back and legs, for example, have fewer receptors with large receptive fields. Receptors with large receptive fields usually have a "hot spot", an area within the receptive field (usually in the center, directly over the receptor) where stimulation produces the most intense response.


Visual system

In the visual system, receptive fields are volumes in visual space. For example, the receptive field of a single photoreceptor is a cone-shaped volume comprising all the visual directions in which light will alter the firing of that cell. Its apex is located in the center of the lens and its base essentially at infinity in visual space. Traditionally, visual receptive fields were portrayed in two dimensions (e.g., as circles, squares, or rectangles), but these are simply slices, cut along the screen on which the researcher presented the stimulus, of the volume of space to which a particular cell will respond. In the case of binocular neurons in the visual cortex, receptive fields do not extend to optical infinity. Instead, they are restricted to a certain interval of distance from the animal, or from where the eyes are fixating (see Panum's area). A photoreceptor, or photoreceptor cell, is a specialized type of neuron found in the eyes retina that is capable of phototransduction. ... Look up apex in Wiktionary, the free dictionary. ... Light from a single point of a distant object and light from a single point of a near object being brought to a focus by changing the curvature of the lens. ... The infinity symbol ∞ in several typefaces. ... Binoculars A set of binoculars (from Latin, bi-, two-, and oculus, eye) is a hand-held tool used to magnify distant objects by passing the image through two adjacent series of lenses, and erecting prisms. ... Brodmann area 17 (primary visual cortex) is shown in red in this image which also shows area 18 (orange) and 19 (yellow) The visual cortex refers to the primary visual cortex (also known as striate cortex or V1) and extrastriate visual cortical areas such as V2, V3, V4, and V5. ...


The receptive field is often identified as the region of the retina where the action of light alters the firing of the neuron. In retinal ganglion cells (see below), this area of the retina would encompass all the photoreceptors, all the rods and cones from one eye that are connected to this particular ganglion cell via bipolar cells, horizontal cells, and amacrine cells. In binocular neurons in the visual cortex, it is necessary to specify the corresponding area in both retinas (one in each eye). Although these can be mapped separately in each retina by shutting one or the other eye, the full influence on the neuron's firing is revealed only when both eyes are open. Human eye cross-sectional view. ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength[1]. The elementary particle that defines light is the photon. ... A photoreceptor, or photoreceptor cell, is a specialized type of neuron found in the eyes retina that is capable of phototransduction. ... Normalised absoption spectra of human rod (R) and cone (S,M,L) cells. ... Normalised absorption spectra of human cone (S,M,L) and rod (R) cells Cone cells, or cones, are cells in the retina of the eye which only function in relatively bright light. ... A human eye. ... As a part of the retina, the bipolar cell exists between photoreceptors (rod cells and cone cells) and ganglion cells. ... Plan of retinal neurons. ... Amacrine cell Retinal cell interneuron interacting at the Inner Plexiform Layer (IPL), the second synaptic retinal layer where bipolar cells and ganglion cells synapse. ...


Hubel and Wiesel (e.g., Hubel, 1963) advanced the theory that receptive fields of cells at one level of the visual system are formed from input by cells at a lower level of the visual system. In this way, small, simple receptive fields could be combined to form large, complex receptive fields. Later theorists elaborated this simple, hierarchical arrangement by allowing cells at one level of the visual system to be influenced by feedback from higher levels.


Receptive fields have been mapped for all levels of the visual system from photoreceptors, to retinal ganglion cells, to lateral geniculate nucleus cells, to visual cortex cells, to extrastriate cortical cells.


Retinal ganglion cells

On center and off center retinal ganglion cells respond oppositely to light in the center and surround of their receptive fields. A strong response means high frequency firing, a weak response is firing at a low frequency, and no response means no action potential is fired.
On center and off center retinal ganglion cells respond oppositely to light in the center and surround of their receptive fields. A strong response means high frequency firing, a weak response is firing at a low frequency, and no response means no action potential is fired.

The organization of ganglion cells' receptive fields, composed of inputs from many rods and cones, provides a way of detecting contrast, and is used for detecting objects' edges. Each receptive field is arranged into a central disk, the "centre", and a concentric ring, the "surround", each region responding oppositely to light. For example, light in the centre might increase the firing of a particular ganglion cell, whereas light in the surround would decrease the firing of that cell. Image File history File links Download high-resolution version (331x606, 36 KB) I made this diagram I, the creator of this work, hereby release it into the public domain. ... A ganglion cell (or sometimes called a gangliocyte) is a type of neuron located in the retina that receives visual information from photoreceptors via various intermediate cells such as bipolar cells, amacrine cells, and horizontal cells. ...


There are two types of ganglion cells: "on-center" and "off-center". An on-center cell is stimulated when the center of its receptive field is exposed to light, and is inhibited when the surround is exposed to light. Off-center cells have just the opposite reaction. Stimulation of the center of an on-center cell's receptive field produces [[depolarization]] and an increase in the firing of the ganglion cell, stimulation of the surround produces a [[Hyperpolarization]] and a decrease in the firing of the cell, and stimulation of both the center and surround produces only a mild response (due to mutual inhibition of center and surround). An off-center cell is stimulated by activation of the surround and inhibited by stimulation of the center (see figure). Surround sound is the concept of expanding the spatial imaging of audio playback from 1 dimension (mono/Left-Right) to 2D or 3D. This is often performed for a more realistic audio environment, actively implemented in cinema sound systems, technical theatre, home entertainment, video arcades, computer gaming, and a growing...


Photoreceptors that are part of the receptive fields of more than one ganglion cell are able to excite or inhibit postsynaptic neurons because they release the neurotransmitter glutamate at their synapses, which can act to depolarize or to hyperpolarize a cell, depending on the ion channels it opens. Illustration of the major elements in a prototypical synapse. ... Chemical structure of D-Aspartic Acid, a common Amino Acid neurotransmitter. ... Glutamate is the anion of glutamic acid. ... Illustration of the major elements in a prototypical synapse. ... Ion channels are pore-forming proteins that help to establish and control the small voltage gradient that exists across the plasma membrane of all living cells (see cell potential) by allowing the flow of ions down their electrochemical gradient. ...


When photoreceptors in the center of an on-center ganglion cell's receptive field are stimulated, they stop releasing glutamate (because photoreceptors are depolarized in the absence of light and respond to light by hyperpolarizing). At their synapses with the on-center cell, glutamate acts as an inhibitory neurotransmitter, opening channels that hyperpolarize the cell. Stopping the release of glutamate inhibits an inhibitory effect, leading to an increase in the firing of the on-centre cell.


Conversely, when photoreceptors in the surround of an on-center ganglion cell's receptive field are stimulated, although they respond by stopping the release of glutamate, at their synapses with the ganglion cell, glutamate acts as an excitatory neurotransmitter, opening channels that depolarize the cell. Stopping the release of glutamate inhibits an excitatory effect, leading to a decrease in the firing of the on-centre cell. A photoreceptor can make synapses with both on-center and off-center cells and thus has synapses in which glutamate is excitatory as well as those in which it is inhibitory.


The center-surround receptive field organization allows ganglion cells to transmit information not merely about whether photoreceptor cells are firing, but also about the differences in firing rates of cells in the center and surround. This allows them to transmit information about contrast. The size of the receptive field governs the spatial frequency of the information: small receptive fields are stimulated by high spatial frequencies, fine detail; large receptive fields are stimulated by low spatial frequencies, coarse detail. Retinal ganglion cell receptive fields convey information about discontinuities in the distribution of light falling on the retina; these often specify the edges of objects. In mathematics, physics, and engineering, spatial frequency is a characteristic of any structure that is periodic across position in space. ...


Lateral geniculate nucleus

Further along in the visual system, groups of ganglion cells form the receptive fields of cells in the lateral geniculate nucleus. Receptive fields are similar to those of ganglion cells, with an antagonistic center-surround system and cells that are either on- or off center. Grays FIG. 719– Hind- and mid-brains; postero-lateral view. ...


Visual cortex

Receptive fields of cells in the visual cortex are larger and have more-complex stimulus requirements than retinal ganglion cells or lateral geniculate nucleus cells. Hubel and Wiesel (e.g., Hubel, 1963) classified receptive fields of cells in the visual cortex into simple cells, complex cells, and hypercomplex cells. Simple cell receptive fields are elongated, for example with an excitatory central oval, and an inhibitory surrounding region, or approximately rectangular, with one long side being excitatory and the other being inhibitory. Images for these receptive fields need to have a particular orientation in order to excite the cell. For complex-cell receptive fields, a correctly oriented bar of light might need to move in a particular direction in order to excite the cell. For hypercomplex receptive fields, the bar might also need to be of a particular length. A simple cell in the primary visual cortex is a cell that responds primarily to oriented edges and gratings (bars of particular orientations). ... Complex cells can be found both in the primary visual cortex (V1) and the secondary visual cortex (V2). ...


Extrastriate visual areas

In extrastriate visual areas, cells can have very large receptive fields requiring very complex images to excite the cell. For example in the inferotemporal cortex, receptive fields cross the midline of visual space and require images such as radial gratings or hands. It is also believed that in the fusiform face area, images of faces excite the cortex more than other images. This property was one of the earliest major results obtained through fMRI (Kanwisher, McDermott and Chun, 1997); the finding was confirmed later at the neuronal level (Tsao, Freiwald, Tootell and Livingstone, 2006). In a similar vein, people have looked for other category-specific areas; some recent research for example suggests the parahippocampal place area might be somewhat specialised for buildings. However, more recent research has suggested that the fusiform face area is specialised not just for faces, but also for any discrete, within-category discrimination. The inferior temporal gyrus is placed below the middle temporal sulcus, and is connected behind with the inferior occipital gyrus; it also extends around the infero-lateral border on to the inferior surface of the temporal lobe, where it is limited by the inferior sulcus. ... The Fusiform face area (FFA) is a part of the human visual system which seems to specialize in facial recognition. ... The parahippocampal gyrus (or hippocampal gyrus) is a grey matter cortical region of the brain that surrounds the hippocampus. ...


References

  • Hubel, D. H. (1963). The visual cortex of the brain. Scientific American, 209(5), 54-62.
  • Kandel E.R., Schwartz, J.H., Jessell, T.M. (2000). Principles of Neural Science, 4th ed., pp.515-520. McGraw-Hill, New York.

  Results from FactBites:
 
Receptive field - Wikipedia, the free encyclopedia (1519 words)
For example, the receptive field of a ganglion cell in the retina of the eye is composed of input from all of the cone cells which synapse with it, and a group of ganglion cells in turn forms the receptive field for a cell in the brain.
The receptive field is often identified as the region of the retina where the action of light alters the firing of the neuron.
Photoreceptors that are part of the receptive fields of more than one ganglion cell are able to excite or inhibit postsynaptic neurons because they release the neurotransmitter glutamate at their synapses, which can act to depolarize or to hyperpolarize a cell, depending on the ion channels it opens.
Journal of Vision - Receptive field structure of H1 horizontal cells in macaque monkey retina, by (10768 words)
Although the pure cone receptive field center is a consequence of the private-line anatomy, the circuitry that mediates the structure and cone composition of the surround is not well understood (Dacey, 1999).
H1 horizontal cell receptive fields were characterized by measuring their responses to drifting sinusoidal gratings as a function of spatial frequency, to flashing spots as a function of spot diameter, and to flashing annuli as a function of annulus inner diameter.
We assumed that the receptive field of the H1 cell was circularly symmetric, that the cell responded to light and contrast in a linear way, that the organization of the H1 receptive fields did not depend on light level, and that the cells were summing inputs from L and M cones only.
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