Evoked Potentials in Clinical Medicine

ONE of the most useful techniques in modern clinical neurophysiology is the recording of evoked potentials. An evoked potential (EP) is an electrical manifestation of the brain's response to an external stimulus. For example, the visual EP produced by the flash of a strobe light can often be seen as a wave in the occipital region in the electroencephalogram. Most EPs, however, cannot be seen in routine electroencephalographic recordings because of their very low amplitudes (0.1 to 20 μV) and their admixture with background brain-wave activity and artifacts.The EP must be extracted from background activity by the technique of . . .