Sense of Touch
The Sense of Touch is one of the five senses in the body and helps us to feel the physical contact with other objects. It, in fact, includes distinct sensory perception, all of which respond to stimuli applied to the skin. It is called a tactile sense. Through touch, we can learn about the shape and hardness of an object and experience warmth, cold pain and pressure.
There are several types of touch organs called tactile corpuscles in the skin and mucous membranes. According to one theory, five different types of nerve endings said to respond to the stimuli of different sensory modalities, have been differentiated as: pain-free nerve endings, pressure-Pacinian corpuscles; cold -Krausse end bulbs, heat – Ruffini endings and touch- Merkel’s discs and Meissner corpuscles. It was found through further experiments that some of these sense organs in the skin respond to more than one type of stimulation.
How the sense of touch works
Sense of Touch organs are found near hair, in areas without hair, and in deeper tissue, the sensation of touch occurs when an object comes in contact with the sense organs and presses them out of shape, or when it touches a nearby hair. The nerves carry impulses from these touch organs to the spinal cord, and from there to the brain.
The touch is more sensitive in some parts of the body than in other parts. This is because the sense organs are not distributed evenly throughout the body. At some places, these sense organs are found in the clusters. The tip of the tongue, of the fingers and the end of the nose are extremely sensitive areas mainly because of the cluster of sense organs present. On the other hand, the back between the shoulder blades contains only a few sense organs per centimetre. That is why these parts are less sensitive to the outside stimuli. The sense organs sensitive to warmth, cold or pain, are also distributed unevenly. Some objects act upon the external stimuli at once. For example, a hot iron would cause pain and heat anywhere in the body.
There are several million points on the body that registers cold, pain, heat or touch. Doctors can map up these points for any given area on a person’s skin which experiences the Sense of Touch.