One physician even remarked that pain is whatever the patient says it is. So let’s just say that pain is a warning sensation to your brain that some type of stimulus is causing or may cause damage, and you should probably do something about it.
Pain perception, or nociception (from the Latin word for “hurt”), is the process by which a painful stimulus is relayed from the site of stimulation to the central nervous system. There are several steps in the nociception process:
- Contact with stimulus — Stimuli can be mechanical (pressure, punctures and cuts) or chemical (burns).
- Reception — A nerve ending senses the stimulus.
- Transmission — A nerve sends the signal to the central nervous system. The relay of information usually involves several neurons within the central nervous system.
- Pain center reception — The brain receives the information for further processing and action.
Nociception uses different neural pathways than normal perception (like light touch, pressure and temperature). With nonpainful stimulation, the first group of neurons to fire are normal somatic receptors. When something causes pain, nociceptors go into action first.