Pain is so common that one in three Americans report experiencing it daily. Their pain varies depending on the person, disease, mental state, and a host of factors that are wholly subjective. None of us is spared from pain.
In its basic elemental form, pain is our body's way of telling us something isn't right. We can classify pain into two types, acute or chronic. Acute pain results mostly from damage to our tissues, through injury, inflammation or disease. It's easily localized, diagnosed, and treated. Chronic pain lasts over an extended period of time and is more difficult to treat. It can be worsened by a person's environment and psychology.
Pain can also be classified into nociceptive and non-nociceptive pain. Nociceptive pain occurs when certain receptors on cells are activated by temperature, vibration, stretching and chemical signals released by damaged cells. One type of pain in this category, somatic pain, is localized and felt when the area is touched or moved and involves musculoskeletal elements of such as skin and muscles. Another is visceral pain which is harder to localize since it involves our internal organs.
The other large category of pain, non-nociceptive, does not require the action of specific receptors and affects the nervous system directly. It can originate in the nervous pathway between the tissue and the spinal cord such as shingles, or between the spinal cord and the brain such as a slipped disc in the spine.
With half a trillion dollars spent annually on pain management, researchers are always looking for new therapies to help ease our pain.