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tactile sensation received by the skin, enabling the organism to detect objects or substances in contact with the body. End organs (nerve endings) in the skin convey the impression to the brain. Touch sensitivity varies in different parts of the body, depending on the number of end organs present in any one area. The tip of the tongue, lips, and fingertips are three of the most sensitive areas, the back and parts of the limbs the least so. The sense of touch is very closely related to the other four sensations received by the skin: pain, pressure, heat, and cold. There is a specific kind of sensory receptor for each of the five so-called cutaneous senses. For example, light-touch receptors convey only the sensation that an object is in contact with the body, while pressure receptors convey the force, or degree, of contact. The blind learn to read by the Braille system by making use of the sensitivity to touch of the fingertips.
The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the ability of animals and man to sense environmental factors by means of receptors in the skin; in the locomotor system, which includes the muscles, tendons, and joints; and in some mucous membranes, such as those on the lips and tongue.

The tactile process is based on stimulation of various types of receptors: mechanoreceptors that perceive contact, pressure, and tension; thermoreceptors that perceive heat and cold; and pain receptors. This information then reaches and is transformed by the central nervous system, including the cerebral cortex. The sensation of touch can be quite varied because it results from a complex perception of different properties of a stimulus acting on the skin and subcutaneous tissues. The perception of environmental objects by touch permits evaluations to be made concerning their shape, size, surface properties, consistency, temperature, dryness or wetness, and position and movement in space. At the cellular level, touch breaks down into several different receptor processes: there is no single morphological type of tactile cell.

The sense of touch greatly broadens the organism’s impressions of its surroundings and plays an important role in its vital activity. In many lower animals the sense of touch, together with chemical sensitivity, is the principal means of perceiving the environment. To some extent, touch substitutes for the sensory organs of sight and hearing when they are injured. Touch permits blind persons to read, perform a variety of delicate manual operations, and orient themselves in space. In persons who are both blind and deaf, touch is the main source of information about the outside world and can be developed to an exceptionally high degree. The term “touch” is becoming less common because of increasing knowledge of the receptor processes’ cellular mechanisms; the mechanisms of mechanoreception, thermoreception, and pain are usually considered independently.


Granit, R. Elektrofiziologicheskoe issledovanie retseptsii. Moscow, 1957. (Translated from English.)
Esakov, A. I., and T. M. Dmitrieva. Neirofiziologicheskie osnovy taktil’nogo vospriiatiia. Moscow, 1971.
Fiziologiia sensornykh sistem, part 2. (Ruko-vodstvopo fiziologii.) Leningrad, 1972.
Milner, P. Fiziologicheskaia psikhologiia. Moscow, 1973. Chapters 8, 10. (Translated from English.)




a performer’s particular manner of producing sound on the piano through various ways of pressing and striking the keys. Each pianist has his own individual touch, which depends on his physiology and artistic intent. J. Field and S. Thalberg produced a soft, “velvety” tone; S. V. Rachmaninoff and A. G. Rubinstein played with a deep, rich tone; and K. N. Igumnov elicited a tender, lyric sound.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


The array of sensations arising from pressure sensitivity of the skin.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


1. Rugby Soccer the area outside the touchlines, beyond which the ball is out of play (esp in the phrase in touch)
2. Archaic
a. an official stamp on metal indicating standard purity
b. the die stamp used to apply this mark
3. a scoring hit in competitive fencing
4. an estimate of the amount of gold in an alloy as obtained by use of a touchstone
5. the technique of fingering a keyboard instrument
6. the quality of the action of a keyboard instrument with regard to the relative ease with which the keys may be depressed
7. Bell-ringing any series of changes where the permutations are fewer in number than for a peal
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005


(1) A generic reference to touchscreen interfaces, which means using the fingers to type, tap icons and move objects on a touch-sensitive screen. See touchscreen and Touch Bar.

(2) See iPod touch.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
References in periodicals archive ?
The workers had been trying to remove an underground oil tank just outside the building and touched off the explosion when the pit they had dug collapsed and pinched a gas line.
The latest sparring between AMP and the market was touched off by newspaper reports in the Australian Financial Review and the Australian that said AMP and NAB were in merger talks.
With their emphasis on missionary work, the LMS sent to Demerara a number of individuals whose behavior touched off the sequence of events that culminated in the revolt of 1823.
Kottke of the Mayo Clinic in Rochester, Minn., touched off a debate between the "primary, secondary, and treatment folks."
(Prop 13 was the ballot initiative in 1978 that put a cap on property tax payments for existing homeowners and touched off a series of similar moves in other states.) The real push behind Prop 13 came from homeowners whose own children were grown and gone and who were peeved by the idea that they should still pay for schools used by someone else's kids.
Chirac's decision last June to cancel the testing moratorium begun by former president Francois Mitterand touched off a storm of protest and condemnation around the world.
The Americans, particularly the 2,500-vessel Alaskan fleet, have been blamed for much of the overfishing of the west coast salmon; this claim has touched off a fishing dispute with the United States.
A few days later, spontaneous combustion touched off a fire inside the sarcophagus.
Two business decisions made recently by the North Bay-based Ontario Northland Transportation Commission (ONTC) have touched off a debate concerning the role of the government agency in Northern Ontario's economy.
It ridicules a literary squabble of the day as to the comparative merits of ancient and modern authors, touched off by Sir William Temple's essay Of Ancient and Modern Learning and continued by Richard Bentley, among others.
Simon Turner Newmarket nap Hot Touch 7.15 Kempton Ran a fine debut when just touched off at Thirsk and has since impressed on the Al Bahathri.
From a slim 38-35 lead in the third quarter, the Blazers touched off a 13-2 run to pull away, 51-37, with 5:42 left in the period.