Localization of visceral pain and other sensations before and after anesthesia

The localization of sensations in sense organs that developed ontogenetically from the ectoderm layer, like vision, hearing, and skin, is much more precise than sensations inside the body, like pain in the chest or viscera, which are produced by receptors developed from the entoderm layer. Pain on the surface of the skin is much more sharply localized than is pain in the viscera. Personal experiences of pain sensations produced by an obstruction in the colon and the effects of anesthesia are described. It became evident that anesthesia can influence the activity of the vestibular organ for many days.