The skin is a particularly fortunate site for studying certain peripheral manifestations of the functioning of the psychic structures originally described by Freud. Indeed, we might say that in a phylogenetic sense the skin is the mother structure of both the id and the ego. "The skin, which in particular parts of the body has become differentiated into sense organs or modified into mucous membrane, and is thus the erotogenic zone par excellence."5 "The ego is first and foremost a body-ego; it is not merely a surface entity, but is itself the projection of a surface."4 An authorized note by the translator amplifies this statement: "The ego is ultimately derived from bodily sensations, chiefly from those springing from the surface of the body."
The study of sensory and perceptual phenomena in their bearing on the total functioning of the organism is by no means new.1 The aim