a characteristic of the receptive fields of many visual and somatosensory neurons in which stimulation in the center of the receptive field evokes opposite responses to stimulation in the periphery. Thus, some neurons depolarize with center stimulation and hyperpolarize when the same stimulus appears in the surrounding region of the receptive field, whereas other neurons have the opposite pattern of responses. Center–surround antagonism greatly increases the sensitivity of the nervous system to contrast. See also off response; on response; simple cell.