Definition: that part of the retina of which the photoreceptors (rods and cones) pertain to a single optic nerve fiber. The response of a neuron to stimulation of its receptive field depends on the type of neuron and the part of the field that is illuminated; an “on-center” neuron is stimulated by light falling at the center of its receptive field and inhibited by light falling at the periphery; an “off-center” neuron reacts in exactly the opposite fashion; that is, it is inhibited by light falling at the center of its receptive field. In either case, the net response depends on a complex switching action in the retina. When an entire receptive field is equally illuminated, the response of receptors at the center of the field predominates.
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Examples: glitazone, GI cocktail, etc.