An attempt for the application of the basic Law of Psychophysics (Fechner-Stevens Law) in the domain of visceral stimuli in humans.

The validity of the basic Law of Psychophysics proposed originally by Fechner and revised by Stevens had been tested in the domain of visceral perception. The experiments were carried out on six adult colonostomy patients. The distension of the sigmoid colon (the phi-value of the Fechner-Stevens equation) had been undertaken by the aid of a rubber balloon inserted into the intestinal stoma orifice and controlled by a computerized pneumatic system. The tracking of sensations of "gut-feelings" by the subjects (the psi-value of the Fechner-Stevens equation) had been made possible by applying the subjects' manipulation of a sliding potentiometer of a Visual Analogue Scale (VAS-device). The results seem to prove the extension of the validity of the Fechner-Stevens power equation to the field of visceral perception.