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Touching
The sense of touch is essential to human development. Infants thrive when they are cuddled and
attended to, but not if they are deprived of human contact (Baysinger, Plubell, & Harlow, 1973;
Feldman, 2007; Haradon, Bascom, Dragomir, & Scripcaru, 1994). [6] Touch communicates
warmth, caring, and support, and is an essential part of the enjoyment we gain from our social
interactions with close others (Field et al., 1997; Kelter, 2009). [7]
The skin, the largest organ in the body, is the sensory organ for touch. The skin contains a
variety of nerve endings, combinations of which respond to particular types of pressures and
temperatures. When you touch different parts of the body, you will find that some areas are more
ticklish, whereas other areas respond more to pain, cold, or heat.
The thousands of nerve endings in the skin respond to four basic sensations:Pressure, hot, cold,
and pain, but only the sensation of pressure has its own specialized receptors. Other sensations
are created by a combination of the other four. For instance:
The experience of a tickle is caused by the stimulation of neighboring pressure receptors.
The experience of heat is caused by the stimulation of hot and cold receptors.
The experience of itching is caused by repeated stimulation of pain receptors.
The experience of wetness is caused by repeated stimulation of cold and pressure receptors.
The skin is important not only in providing information about touch and temperature but also
in proprioception—the ability to sense the position and movement of our body parts.
Proprioception is accomplished by specialized neurons located in the skin, joints, bones, ears,
and tendons, which send messages about the compression and the contraction of muscles
throughout the body. Without this feedback from our bones and muscles, we would be unable to
play sports, walk, or even stand upright.
The ability to keep track of where the body is moving is also provided by thevestibular system, a
set of liquid-filled areas in the inner ear that monitors the head’s position and movement,