There are more evoked potentials, such as visual, brainstem auditory, event-related potentials, and somatosensory evoked potentials. Visual evoked potentials are mainly for optic nerve disorders. Brainstem auditory evoked potentials are mainly used to determine auditory nerve and brainstem injuries and coma patients. Somatosensory evoked potentials, mainly for deep sensory detection, such as spinal cord injury, evoked, can understand the approximate location of the injury. Event-related potentials, mainly for cognitive function judgment, such as some dementia patients through the P300 potential, can determine whether there is cognitive decline.