So far, you have learned about the location and size of RFs. Here we look at the structure of RFs . According to the traditional view, the receptive field is defined as the area on the receptor surface within which stimulation elicits neuronal responses .
Lateral inhibition enhances contrast between stimuli.
Ganglion cell receptive fields have a center and antagonistic surround. Two classes of ganglion cells can be distinguished by their response to a small spot of light applied at the center of their receptive field. ON center cells signal rapid increases in light intensity, and OFF center cells signal rapid decreases. The absolute amount of light reflected by objects is relatively uninformative because it is determined by the intensity of the light source. The information required to detect objects is contained mainly in variations in the light intensity across the visual scene.