Final answer:
Pain is the neural processing of injurious stimuli in response to tissue damage. It can be caused by true sources of injury or harmless stimuli that mimic damaging stimuli. Nociception starts at sensory receptors and the neural signal undergoes final processing in the primary somatosensory cortex. Treatment options for interrupting pain transmission include relaxation therapy, analgesic medications, and deep brain stimulation. Chronic pain can be caused by chemical messengers associated with the immune response.
Step-by-step explanation:
Pain is the name given to nociception, which is the neural processing of injurious stimuli in response to tissue damage. Pain can be caused by true sources of injury, such as thermal burns or contact with corrosive chemicals. It can also be caused by harmless stimuli that mimic damaging stimuli, such as contact with capsaicins. These compounds activate the same calcium channels that are activated by warm receptors.
Nociception starts at the sensory receptors and the neural signal undergoes final processing in the primary somatosensory cortex. One of the nociceptive pathways projects directly to the hypothalamus, which modulates the cardiovascular and neuroendocrine functions of the autonomic nervous system. Pain can also stimulate the sympathetic branch of the visceral sensory system, preparing the body for a fight-or-flight response.
Interrupting pain transmission at the site of injury can be done through various treatment options, ranging from relaxation therapy to analgesic medications to deep brain stimulation. Chronic pain, which often persists after tissue healing, can be caused by chemical messengers associated with the immune response. These messengers can cause sterile inflammation and stimulate pain receptors.