Physical touch has many meanings than skin-deep. For example, a simple touch like a hand on a shoulder, or an arm around a waist can reduce heart rate lower blood pressure. Even people in deep coma may show changes in their heart rates when their hands are held. Positive touch appears to stimulate the release of endorphins, and the body’s natural pain suppressors. That may explain why a mother’s hug can cure it better  when a child skins his knee.