SINCE the psychogalvanic reflex, or Fere's phenomenon, was first described, in 1888,1 there has been a continued and increasing interest in the study of the electrical resistance of the skin, first in Europe and since the 1920's in this country. For over twenty years the investigations of Richter1 have served as the basis for studies of skin resistance in the United States. Used first by psychiatrists in an attempt to characterize certain psychopathic states, the electrical resistance of the skin has become important to surgeons dealing with the nervous system, particularly to those dealing with the sympathetic nervous system and with injuries of the peripheral nerves.
"The resistance offered by the body to the passage of a delicate constant current is localized almost entirely in the skin. This is shown quite conclusively by the fact that a minute puncture through the skin causes the resistance to drop from