Pain is simply the way we come to know about damage to the body’s tissues, and the feeling it produces differs according to how the brain interprets it. Our brains can present knowledge as anything from intensely unpleasant to just another piece of sensory information. And we all can turn the first experience into the second, whether by using drugs or altering our thinking.
Nerves distributed around the body run up the spine and into the brain, where they are registered in the somatosensory cortex. It used to be thought that pain information traveled up the nerve pathways and was automatically felt as pain once it reached the brain, but now a more complicated picture has emerged.
When you bang your shin, your automatic response is to rub it. ‘Rubbing it better’ works because the receptors and nerve fibers that transmit pain messages lie close to those carrying sensations such as warmth and pleasant touch. If non-pain fibers next to a pain-carrying fiber are stimulated, the signals from the pain nerves are blocked before they are consciously registered. The pain blockade occurs because only one type of sensation can be felt in the same area of the body at the same time.
The ‘competition for consciousness’ between painful and pleasant stimuli was first discovered in the 1960s by physiologists Patrick Wall and Ronald Melzack. Their ‘gate control ‘ theory of pain proposed that there was a ‘ gate’ in the spinal cord, which allowed only one type of sensation to pass through it at a time. However, recent research suggests that the gate effect is, in fact, provided by the body’s attention system.
Attention to pain
An area of the brain called the cingulate cortex, which lies in the groove between the brain’s two hemispheres, can turn attention inwards or outwards. If something threatening or exciting is going on, the cingulate cortex switches your attention away from your body and reduces any sensation of pain. This is one reason why soldiers wounded in battle may feel no pain at the time, as their minds are occupied elsewhere. It has even been reported that up to 20 percent of people who undergo major surgery report feeling little or no pain for hours or days after the operation.
Prolonged severe pain, as may occur in a chronic condition such as sciatica, can have a debilitating effect by reducing a person’s mental ability to cope with the continuous discomfort. The sufferer can come to focus increasingly on the pain; this makes it seem more and more severe as each unpleasant sensation is amplified. Studies have shown that about 70 percent of people who suffer from chronic lower back pain do not have any readily detectable injury.
The brain’s painkillers
The brain produces its natural painkillers – a group of chemicals called endorphins. These relieve pain by increasing levels of dopamine, another brain chemical that enhances feelings of well-being. Other chemicals help to prevent pain from being laid down in the brain. Oxytocin, for example, is a hormone that women produce during labor, and one of its functions is to reduce the memory of the pain of childbirth.
Pain thresholds
Sensitivity to pain differs from person to person and from culture to culture. You can test your pain threshold by holding your hand in freezing water. How long does it take before it starts to hurt, And when does it become unbearable? Most people cannot manage more than two or three minutes. Such experiments have tended to suggest that women have lower thresholds than men. Still, the findings are difficult to interpret – it may be that men are socially conditioned to appear brave under such circumstances, or they choose to interpret certain stimuli as discomfort rather than pain. Other studies show that Mediterra people report pain in response to a stimulus that the Europeans describe as merely unpleasant. This may reflect a biological difference or merely demonstrate that some cultures encourage expression while others inhibit it.
Dealing with pain
Hypnosis, relaxation, meditation, and behavioral modification can all reduce the experience of pain by turning a person’s attention away from it. The effect of attention was dramatically demonstrated in a study in which patients were hypnotized before being operated on without anesthetic. They were told they would feel no pain but that a ‘ hidden observer’ in their mind would feel it for them. After surgery, the patients reported feeling nothing. But when the hypnotist addressed the ‘ observer,’ they reported excruciating pain. This suggests that, in some conditions, we can dissociate from pain, even though it is laid down in the brain.
Conversely, pain can be made worse by fear and anticipation. If a person has experienced severe pain during a particular procedure in the past – having a tooth filled at the dentist’s, say – it can create the expectation (sometimes unconscious) of suffering in the same way again. This will make that person attend more closely to their feelings next time they go to the dentist, and the attention will make the new experience even more painful. In cases like this, psychotherapy may help to uncover such unconscious expectations and give the person the ability to divert their attention from painful stimuli in a future situation.
Refocusing attention away from pain is a technique used by practitioners of yoga, for example, who are able to achieve such feats of endurance as lying on a bed of nails or walking barefoot across red-hot coals. By ‘retaining’ their brains through meditation, they have managed to reduce the significance of pain signals to a point where they do not experience pain in the same way as an ordinary person.
Pain medication
Although our sensation of pain is very much dependent on our expectations, mental state, and psychological makeup, there is much that can be done medically to help people deal with pain, both short and long-term. There is a wide range of pain-killing – or, more accurately, pain-relieving – drugs available, which can be extremely beneficial in many cases. These either act at the site of the pain or act in the brain by interfering with the pathways that bring pain to conscious attention. The most suitable analgesic will depend on the cause and nature of the pain, but if the pain is persistent or severe, a doctor’s advice should be sought.
Pain Meditation
Meditation can help you dissociate yourself from pain. Even if it’s there, you don’t have to suffer too much. There are many techniques, so experiment to find which works best for you. Here are four options:
- Concentrate on your breathing. Take long, deep inhalations and focus on the feeling of each one.
- Focus on the part of the body distant from the pain: if the pain is in your right side, focus on the left; if it’s in your head, focus on your feet. This technique works particularly well with migraine: if, for example, your migraine is on the right side, focus on the left side of your body, from the neck down.
- Close your eyes and imagine you are in some beautiful, peaceful place where there is no pain.
- If the pain is so overwhelming that you cannot focus on anything else, try a little self-induced dissociation. Close your eyes, and imagine the pain as a physical object. Concentrate on exactly where the pain is, measuring its dimensions and shape. When its form is clear in your mind, imagine wrapping it up in brown paper and tying some string around it. Then imagine taking his ‘parcel’ out of your body and lacing it a long way away. Place it on the ground. Then, walk away from it. These types of mind control may sound too simple to be effective, but with practice, they really can work. If you succeed, you will find that the feeling of pain, although still there, ceases to bother you as much as before.
Common painkillers
- Painkillers, or analgesics, are among the most commonly prescribed drugs.
- Analgesics are classified into non-opioid – including over-the remedies such as aspirin and paracetamol – and opioids, such as morphine.
- Generally, non-opioid analgesics are more suited for mild to moderate muscle or joint pain. Opioid analgesics are usually used to combat moderate to severe pain, particularly when it is internal in origin.
- Aspirin is used to treat headaches, acute pain, painful menstruation, and fever. It is also an effective anti inflammatory. It may cause stomach irritation, so it is best taken after food.
- Paracetamol is similar in effect to aspirin and is often preferred, especially in older people – as it is less irritating to the stomach.
- Of the opioid analgesics, morphine is the most effective for severe pain, although nausea and vomiting are common side effects. Other opioids include codeine, which is effective for the short-term treatment of mild to moderate pain, and diamorphine (heroin), a powerful narcotic drug.
