Pain

[Ready for Fall 2026]

Modified: 2026-07-29 2:27 PM CDST

• The receptors for pain are free nerve endings in the skin.
  • Those free nerve endings cover most but not all of the skin.
  • So, it is possible to find parts of your skin that do not respond to pain.

• Billions of dollars are spent each year to treat pain as a symptom.
• Much of that money is spent on:
  • drugs,
  • hypnosis,
  • and TENS (transcutaneous electrical nerve stimulation) units (they are attached to the affected area, and deliver mild shocks in response to the pain).
  • In some cases, surgery is indicated, and nerves may be cut to relieve pain.
• Behavioral management is also used.
  • Participants may be taught to ignore pain.
  • Six ways to use your mind to control pain
• The environment can affect pain.
  • During World War II surgeons found that soldiers required much less morphine than prewar civilian patients did.
    • Doctors attributed that difference to the differences in perception of both groups.
    • To civilians, going to the hospital is an unwelcome experience and they expect pain.
    • However, to soldiers in battle, going to the hospital is a welcome experience.
    • Their feelings are of relief, not of dread.
  • So, pain can be affected by the environment, and that probably forms the basis for behavioral treatments for pain.
• The physiology of pain is has been described by gate theory.
  • In gate theory, two types of pain pathways are proposed.
    • One type conducts the pain impulse quickly, the other slowly.
    • They both come into a "gate."
    • Usually we cannot prevent the fast-acting pain from being detected.
    • However, gate theory says that if the gate is stimulated, say by rubbing, then the slow-acting pathway will be closed.
  • Take the following example.
    • You hit your thumb with a hammer by accident.
    • Then you quickly rub your thumb. By doing that you may close the slow-acting pathways, and not feel throbbing pain in your thumb later.
• Drugs that relieve pain are called analgesics.
  • Aspirin and tylenol are analgesics.
  • So is morphine, a very powerful analgesic.
    • Unfortunately, morphine also has addictive properties.
  • Endorphins are analgesics manufactured by the body.
    • They are produced in response to pain and they may account for individual differences in pain perception.
    • One person may just produce more endorphins than another in response to the same painful stimulus, and thus report less pain.
• Anesthetics are drugs that deaden all of the skin senses.
  • When you go to the dentist for a tooth extraction or cavity, you will get an anesthetic, novacaine.
  • Novacaine causes you not to feel pain, touch, hot, or cold.
  • So, when you attempt to put a little water into your mouth to rinse it, you cannot keep your lips on the cup easily, or feel the cup.
• I was shocked when a surgeon once injected me with xylocaine, (a fast-acting anesthetic) and immediately picked up his scalpel.
  • I thought he would wait awhile, but he assured me he did not need to, and proceeded to remove a small abscess, without my feeling anything.
  • I watched as he painlessly cut my arm, bled, and later sutured the wound.