Elektrophysiological methods provide objective data about the function of the somatosensory system. Broadly established methods like neurography, myography, sensory evoked potentials and electrically evoked reflexes are in contrast to less well known techniques as laser-evoked potentials and microneurography. It is important to keep in mind that neurography and sensory evoked potentials comprise the function of myelinated nerve fibers with big axonal diameters. Unlike, laser-evoked potentials and microneurography describe the functionality of nonmyelinated, small diameter nerve fibers, which transmit pain and temperatures as sensory signals. Investigation of the sympathetic sudomotoric system can provide evidence for lesions within sympathetic nerves.