Editing Receptive field (section)

{{short description|Delimited medium where some stimuli can evoke neuronal responses}}
{{Distinguish|Reflexogenous zone}}
The '''receptive field''', or '''sensory space''', is a delimited medium where some [[Stimulus (physiology)|physiological stimuli]] can evoke a [[Sensory neuron|sensory]] neuronal response in specific [[organism]]s.<ref name="Alonso&2008">{{cite journal|last1 = Alonso|first1 = J.-M.|last2 = Chen|first2 = Y.|year = 2008|title = Receptive field|journal = Scholarpedia|volume = 4|issue = 1|page = 5393|doi = 10.4249/scholarpedia.5393|doi-access = free}}</ref>

Complexity of the receptive field ranges from the unidimensional [[chemical structure]] of [[odorant]]s to the multidimensional [[spacetime]] of human [[visual field]], through the bidimensional [[skin]] surface, being a receptive field for [[touch]] perception. Receptive fields can positively or negatively alter the [[membrane potential]] with or without affecting the rate of [[action potential]]s.<ref name="Alonso&2008" />

A sensory space can be dependent of an animal's location. For a particular sound wave traveling in an appropriate [[transmission medium]], by means of [[sound localization]], an auditory space would amount to a [[reference system]] that continuously shifts as the animal moves (taking into consideration the space inside the ears as well). Conversely, receptive fields can be largely independent of the animal's location, as in the case of [[place cells]]. A sensory space can also map into a particular region on an animal's body. For example, it could be a hair in the [[cochlea]] or a piece of skin, retina, or tongue or other part of an animal's body. Receptive fields have been identified for neurons of the [[auditory system]], the [[somatosensory system]], and the [[visual system]].

The term ''receptive field'' was first used by [[Charles Scott Sherrington|Sherrington]] in 1906 to describe the area of skin from which a [[scratch reflex]] could be elicited in a dog.<ref name="Sherrington1906">{{cite journal|last1 = Sherrington|first1 = C. S.|year = 1906|title = Observations on the scratch-reflex in the spinal dog|url = http://jp.physoc.org/content/34/1-2/1.full.pdf+html|journal = Journal of Physiology|volume = 34|issue = 1–2|pages = 1–50|doi=10.1113/jphysiol.1906.sp001139|pmid = 16992835|pmc = 1465804 }}</ref> In 1938, [[Haldan Keffer Hartline|Hartline]] started to apply the term to single neurons, this time from the [[frog]] [[retina]].<ref name="Alonso&2008" />

This concept of receptive fields can be extended further up the nervous system. If many sensory receptors all form [[synapses]] with a single [[cell (biology)|cell]] further up, they collectively form the receptive field of that cell. For example, the receptive field of a [[retinal ganglion cell|ganglion cell]] in the retina of the eye is composed of input from all of the [[photoreceptor cell|photoreceptors]] 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.

Receptive fields have been used in modern artificial [[deep neural networks]] that work with local operations.