Your sense of touch usually pulls you away from the prick of a needle. But practitioners of acupuncture -- a form of therapy that involves sticking the patient in certain places with very thin needles -- have been poking patients for thousands of years. Acupuncture's origins can be traced back to ancient China. Pin-pricking proponents of acupuncture believe that the correct placement of needles in the patient's skin can restore the body to a healthy balance [source: Mayo Clinic].

Psychology of Touching

You probably already know a hug from a loved one can lower your blood pressure and make you feel valued and important. A firm handshake with a friend can create a connection. How you perceive the hug or handshake, along with how your touch receptors receive the pressure, is rooted in your brain.

There are several basic kinds of touch that you may experience:

  • Intimate -- Here, your pressure receptors respond to a handshake, hug or kiss. If the person giving the touch is someone you care about, you'll probably feel warm and comforted. Your pressure sensors send the feeling of how hard the embrace is, and your brain interprets the nature of the touch as soothing [source: A.D.A.M.].
  • Healing or therapeutic -- This type of touch is often associated with massage or acupuncture. Sometimes, the pressure is gentle and meant to soothe sore muscles. Other times, the pressure is deep in order to work out knots. Despite differences in severity of pressure, you likely to be aware that the outcome is healing, so your body allows you to relax.
  • Exploratory or inquisitive -- We all learn about the world through our sense of touch. Many people test out foods, fabrics or other objects by feeling different textures. Sometimes it's possible to rely solely on the sense of touch. This is why it's easy for you to reach into your bag and find a pair of keys without looking. You know the cold feeling of the metal key and hard smooth feel of your plastic key chain.
  • Aggressive or painful -- Of course, we all know that touch can also equate to pain if the pressure is too much and the intent is wrong. A handshake that's too firm can be uncomfortable instead of reassuring.

Your sense of touch is not only related to your nerve endings undergoing stimulation; the way you interpret the touch is also important. For lots more information on the sense of touch, see the links on the next page.