 the receptive field of an individual sensory neuron is the particular part of the body surface in which a stimulus will trigger the firing of that neuron. this surface can be a hair in the cochlea or a piece of skin, retina, tongue or other part of an animal's body. additionally, it can be the space surrounding an animal, such as an area of auditory space that is fixed in a reference system based on the ears but that moves with the animal as it moves (the space inside the ears), or in a fixed location in space that is largely independent of the animal's location (place cells). 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 sherrington (1906)"sherrington, c. s. (1906). observations on the scratch-reflex in the spinal dog. journal of physiology, 34, 1-50. retrieved from http://jp.physoc.org/content/34/1-2/1.full.pdf+html to describe the area of skin from which a scratch reflex could be elicited in a dog. according to alonso and chen (2008) "alonso, j.-m., & chen, y. (2008). receptive field. scholarpedia, 4(1), 5393. doi: 10.4249/scholarpedia.5393 retrieved from http://www.scholarpedia.org/article/receptive_field it was hartline (1938) who applied the terms to single neurons, in this case from the retina of a frog. the concept of receptive fields can be extended further up to 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 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. ==auditory system== in the auditory system, receptive fields can correspond to volumes in auditory space, or to 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. ==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. 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 (up to 500 per cubic cm) mechanoreceptors with small receptive fields (around 10 square mm), while the back and legs, for example, have fewer receptors 
Sensory_systems